I turn the lights on when I get up in the a.m. (around 6a), then off when I've eaten and done the dishes (around 8p). The longer your tortoise's days are, the more he wants to stay awake and not sleep. For a hibernating species this is important, if you're planning to keep him up during the winter.
For my RES I keep his MVB on from 7-8pm. He always knows when it's bedtime because it's on a timer. He basks like 1/2hr before lights out and then gets in his spot for sleeping. I guess it's an internal clock because he does it every single night. My Beardies did the same thing. They just knew when the light was about to turn off.
I guess I'm saying a it's good to be consistent.
Tyler, That sounds fine, you can kinda watch your tort and see if he likes that schedule. i have my sulcatas lights on a timer they come on at 9am and shut off at 10 pm. that allows me to spend more time with him when i get off work. AS soon as the lights kick on at 9am he wakes up walks around then goes back under his Ceramic heater for about another half hour until his MVB basking spot warms fully up. Then for bed time right around 9 pm he starts digging in for the night.
For an equatorial (or close to it) species like a redfoot, a 12 hour cycle is best in my opinion. I do my Gpp 10 hours in the winter and 14 hours in the summer. I do my baby sulcatas around 12 hours a day year round, but my adults live outside and get the natural Southern CA light cycles.