Check out the sleeping chart at Babycenter http://www.babycenter.com/0_how-much-sleep-does-your-chil...
For a 7 month old, it says she should be getting 11 hrs at night and about 3 hrs during the day for naps (14hrs total per day).
I have been using this chart for my daughter who is now 9 months old. It's pretty right on for her. I usually just stick to a schedule. She usually takes 2 naps during the day (a morning nap around 10am and an afternoon nap around 2pm). Her naps have gradually gotten longer. They used to last only about 45 minutes, but now are lasting about 1.5 hrs. We just transition to 2 naps per day. Up until 8 months she was taking 3 naps. I usually put her down for her naps awake. She might fuss a bit, but she knows now what she is suppose to do. She eventually falls asleep. If she is being really fussy, I'll put a toy in her crib to keep her busy until she falls asleep. If I let her fall asleep on me first, she'll wake up when I put her in her crib and won't fall back asleep.
Now that my daughter is crawling, she has been getting really upset when I put her down for the night because she wants to play and be on the floor. I am not a huge fan of letting her get hysterical before bed, especially because she's never really given me a problem in the past. What I've been doing, that seems to be working is... when she is pretty upset, I'll pick her up and stand close to her crib, see if she has any burps or if anything is bothering her. Sometimes she tries to get me to put her on the floor, but I make sure I don't give in. By standing close to her crib, I think she just knows that she has no choice but to go to bed. I give her a minute to calm down then I put her right back in her crib. If she gets upset again, I'll do the same thing. I usually don't have to pick her up more than twice.
Good luck. I know all babies are different and some things work and some things don't. I hope you find something that works.