Give it as large an enclosure as you can since Russian's are VERY active torts. Put in numerous rocks they can climb over, curved slate shingles they can dig under, a ceramic water bowl, a basking spot around 90-95 degrees, and a cool spot around 70-75. Keep it above 65 at night until your charge has been checked out by a vet and is worm/parasite free then you should drop it to 55-60 at night. Russian's can have GI trac issues if you keep it too warm at night. They can take temps into the high 30's/low 40's at night (which our group regularly experiences in late September through October until I bring them in to hibernate) as long as they can warm up during the day. When healthy they are a very hardy tortoise and IMHO the hardiest.
Feed it a good salad mix. Here's our recipe and it will give you firm stool, high Calcium to Phosphours ratio, and fiber content above 25%. Those are all needs for your tort.
50% Dandelions, 20% Grape leaves, 20% any local weed like plantain or mallo or Turnip greens, 10% chopped opuntia cactus pads. In the winter (when not hibernating) grape leaves and weeds are hard to find so mix in Romaine lettuce, escarole, or Collard greens. Stay away from Cabbage, Spinach, and all the other crud people say it's okay to feed them and you'll be fine. If you can get him to eat it a little Mazuri Tort chow is okay on occasion. (That's my plug for Ed.)
Once the weather stays above 65 during the day and above 50 at night put it outside. Outdoors is a must for Russian's. They do not do well kept indoors for long periods of time. Ours are indoors only 3-4 months of the year (we live in Minnesota)and after 2 months they are battling with one another and generally miserable even in our large enclosures. Once they are put outside in late April they couldn't be happier.
Good luck.
Ernie