From Naivasha town, take the right hand turning down South Lake Road.
After approx 20 mins, you will pass Sopa Lodge on the right, followed by Longonot Farm.
The Kilimandege Sanctuary is the next gate on the right (has a metal vulture on the front and a sign with the initials 'JR').
If you reach Simba Lodge, you have gone too far!
Typing 'Otter Cottage, Naivasha' into google maps will also give you the rough location of the gate.