Hi,
I know you may have gotten advice already but I have a few tips too!
Your LO should sleep about 16 hours TOTAL! Usually you want 11 or 12 of those hours to be at night. So start to monitor how much she is sleeping during the day and if at times you think she has already hit her quota of 4 or 5 hours of naps then do what you can to keep her awake until bedtime. Also, try not to let her nap too close to bed time, at least 2 hours between her last nap and bedtime.
Another thing is, if you haven't already, try to establish a wind down routine. For example give her a bath with dim lights or soft music, etc, not too much stimulation. I found it very hard and still do find it hard to have a routine or schedule, but our bed time routine is one I try to never stray from! My LO was probably 2 months old before I realized this but it definitely helps!
Good luck!