last February I crossed from Miyawaddy to Mae Sot. I took a share taxi at 8 am (booked from the hotel) from Hpa an. Safe trip and friendly border. From Mae Sot I proceeded by song taew, minibus and bus to Bangkok for 11 euro and arrived at the bus station in BKK at 11 pm.
You can also fly from Mae Sot (nok air) to Bangkok (DMK) starting from 23 euro.
If you want to go to Laos you can go by land from Mae Sot to Chiang Mai.
From Chiang Mai to Luang Prabang the usual route is bus to Chong Kong, cross border and sleep in Huay Xay then boat along Mekong river (2 days) from Huay Xai to Luang Prabang, but, given your timetable, I would fly direct Chiang Mai - Luang Prabang

"2 days in Bangkok. 2 days in Ayutthaya. 2 days in Lopburi. 2 days in Phitsanoluk. 2 days in Chiang Mai. 2 days in Pai. 2 days in Mae Hong son. 1 day in Chiang Mai. 3 days in Koh Samui. 2 days in Koh Phangnan. 2 days in Koh Tao. 3 days in Khao Sok. 2 days in Krabi then i don't know, maybe to Phuket for 3 days and flight back to Bangkok."
I would suggest
Bangkok 4 nights (daytrip to ayuthaya)
Kanchanaburi 2 nights
Chiang Rai 3 nights (incl overnight tour)
Chiang Mai 4 nights
2 nights overnight trek extra
Fly Krabi 4 nights
Lanta 4 nights
Mook 3 nights
Trang 2 nights
Fly back to Bangkok.
Much better.

Don't bank on getting any work in those countries. Take enough money with you for the trip. If you need to work, a TEFL qualification would probably help, as would teaching experience. What can you do that a local can't? It is probably easiest to earn money at home, and travel cheaply. In Thailand it is illegal to work without a work visa. I have seen foreigners handing out flyers in Sihanoukville and Luang phabang, but S E Asia isn't really the best place to work your way around.

A lot of information we found online and in guidebooks beforehand was outdated and/or conflicting, so here's detailed updated info on taking the bus from Thanh Hoa, Vietnam, to Sam Neua, Laos, and the situation at the Na Meo / Nam Soi border crossing, as of 23 November, 2019.
Short version: Bus left at 8:15, cost 500K dong, took 9 hours. Visa on arrival for Laos is available now, but will NOT be in 2020.
Long version:
The bus leaves Thanh Hoa from the Western bus station, "Ben xe phia Tay", between Nguyen Trai and Nguyen Xuen Khoat streets, about 1 km south of the railway station. There is no ticket office, booth, or desk of any kind here, so no way to book or buy tickets before getting on the bus. No information on schedules or prices either. It's just a parking lot with bathrooms and food stalls.
We took the bus on a Sunday, so it probably leaves every day. There were actually three identical buses (Quang Ninh company midibus with 25 seats) leaving towards Laos in the morning, but apparently only one goes all the way to Sam Neua.
Some information online suggests that there may be a (different?) bus leaving from the main Thanh Hoa bus station Tuesday-Saturday, but we have no confirmation about that.
We had read that the bus may fill up and leave well before the scheduled 8:00 departure time, so we arrived at 06:50. However, there was nobody on the bus yet. They started packing the bus with cargo around 07:15, and most passengers arrived 07:30-07:45. The aisles and backseat were filled with rice sacks and other cargo, but several seats were vacant when we departed. Things may well be different other times of the year or on other days of the week. The bus left at 08:15.
As for the price, the driver and conductor quoted us 500K dong per person when we asked about it before getting on the bus, and that's what we paid. No tickets or receipts.
There may be some foreigner extra in this price, as we saw a woman going all the way to Sam Neua pay 400K. However, 500K dong is fairly close to the posted price in the other direction (Sam Neua -> Thanh Hoa), 180K kip, so it's not really a big scam or anything. In any case, it's best to confirm the price before getting on.
There was a bathroom break at 9:30 and we stopped for lunch for 15-20 mins around 11. The roads are fairly good, though serpentine and a bit bumpy on the Vietnamese side.
We reached the border in good time at 13:45. Border formalities were effortless in Vietnam. After being stamped out of Vietnam, you need to walk (without your main luggage) a few hundred meters across no-man's land to the Lao immigration offices. The bus will wait for you there.
Lao formalities were fairly quick also. Did not have to pay any additional $1 tourism fee, although there are posters about such.
Now in November 2019 visas on arrival for Laos ARE still available at this crossing (Na Meo - Nam Soi). However, Lao authorities have notified that after December 31, 2019 visas on arrival will NOT be available here anymore (see, e. g., https://laotiantimes.com/2019/10/18/nine-border-checkpoints-to-discontinue-visa-on-arrival-services/).
We had organized visas beforehand at the Lao embassy in Hanoi, which was easy and quick (got them in 15 mins while we waited).
The bus left the border area around 14:20. The road was far, far worse on the Lao side, especially for the first 20 km or so. They appear to be still fixing the results of major landslides earlier this year. At one point, we were held up for 25 mins waiting for such clearing work.
Still, we arrived in Sam Neua around 17:15, so the trip took around 9 hours total. This bus only stops at the inconvenient Nathong bus station, around 4 km outside town and does not enter the centre of Sam Neua. A single taxi was there and took us to town for 20K kip, waiting at the ATM while we withdrew the cash.
So, unlike some have suggested in past years, a pretty straightforward trip in the end with no major scams or problems. But in the near future, you will need to have a Lao visa beforehand.

Do you know if I can apply at the Embassy in Myanmar, get rejected and then try again in Thailand for example? I heard Chiang mai is an option.
In principle you can, whether it makes sense I don't know. But as policy varies I'ld say yes but of course it also depends on why it is rejected. I've no experience with obtaining chinese visa abroad so you best do a bit of research but my approach would be to see where things seem easiest among the convenient locations and apply where you have the best chances.
Can I get a visa without plane tickets and can I lie about my itinerary?
Not sure about the plane tickets, but from a neighboring country overland travel (so no plane tickets)seems reasonable to me. The itinerary can be complete fake no-one will check as far as I can judge. What is asked with respect to the itinerary can vary wildly in my experience. Sometimes mentioning the provinces to visit was enough, but I've also experienced they wanted a day to day plan supported with hotel bookings for every single night and air tickets.

Planning on visiting the Philippines for about 2 months and wondering which town/city is considered to be the cheapest. Something equivalent to Yogyakarta in Indonesia, or maybe Chiang Mai in Thailand, or Dalat in Vietnam.
My budget is adjustable to whatever is considered the cheapest. To give you an idea though, USD $2-4/day was what i paid for accommodation in the above mentioned cities, and they came with AC, double bed, toiletries, 2 bottles of water and western toilet (mostly private too). So basically, that's my requirement... and the place to not be so rural that i would be the only foreigner they'd seen in a while.
It's not really a vacation so i won't be going out except to grab something to eat. I will be working through my computer, just need a cheap different place to complete my work. So expenses will basically be:
1) Food (local/street food if its clean. Ramen noodles and boiled eggs if not. Completely OK with that)
2) Soda
3) Toiletries
3) Public transportation (in case i need to get somewhere. Wont be necessary if food is close to accommodation)
4) Internet
And thats it.
Any suggestions?
You are welcome.
I was actually suggesting to start your trip in Chiang Mai (and just fly via Bangkok) and keep Bangkok for later on. Because Chiang Mai is more relaxing than Bangkok.
Its 3 hours from Koh Samet to Bangkok, so not further than Hua Hin (but the beaches are nicer). Or you could end up on Koh Chang on day 12, and your friend spends 2-3 days on the beach with you, travels by transfer / ferry / transfer to Trat airport (about one hour) and flies out of Thailand (Trat - Bangkok - home). Koh Chang is even better in terms of beaches than Koh Samet and get less "weekend visitors".
Hello
I'll be visiting China in March 2018 starting in Yangshuo and finishing in Yuanyang Rice Terrace before heading to Luang Prabang by bus. I was wondering if it was possible to buy the bus tickets from Kunming to Yuanyang and from Kunming to Luang Prabang in any travel agency in Yangshuo or Guilin. I'm afraid there's not availability for the dates I want to travel.
Cheers