Matatus heading north towards Kitale can drop you at the access road, about 18km north of Kakamega town (KSh100). It's a well-signposted 2km walk from there to the park office and Udo’s.
Regular matatus link Kakamega with Shinyalu (KSh90), but few go on to Isecheno. Shinyalu is also accessed by a rare matatu service from Khayega. From Shinyalu you will probably need to take a boda-boda (motorcycle taxi) to Isecheno (KSh100).
The improved roads are still treacherous after rain and you may prefer to walk once you’ve seen the trouble vehicles can have. Shinyalu is about 7km from Khayega and 10km from Kakamega. From Shinyalu it's 5km to Isecheno.
The dirt road from Isecheno continues east to Kapsabet, but transport is rare.