Be strong. Give your child a five minute warning prior to starting her bedtime routine. Have a consistent routine which is pleasurable for you both. Make sure you move things along regardless of delaying. Select a bedtime which allows for a total of 12-13 hours of sleep per day including naps, recognizing that her am wake time is likely constant. Put her in bed at the appointed time.
Change your focus. As others have mentioned, comforting routeins & settling rituals are important. Avoid daytime naps of more than 2-3 hrs at a time so she isn't getting deep sleep during the day & shorten them if needed. Be firm about night time & leave her.I'm less concerned about when she lays down to sleep than about her staying in her room. Most will stay put if they know you will close the door if they wander.
Bedtime routine. First of all you need to determine what is an appropriate bedtime for your daughter. Different children require different amounts of sleep. If your child is tired but fighting sleep then it is time for bed. Try to create a bedtime routine which gradually relaxes the child before bedtime. This may entail a warm bath and story time. Vigorous play or exciting tv or video games should be avoided.
Bedtime routine. The key is to get her to settle down with a consistent routine at bedtime. First we wash up, then we brush teeth, then we change into pjs then we read a book then we go to bed or something like that.
Out-Persist Her! To quote my wife, "if they don't fight, they're not worth keeping." smart kids will continue stalling if there's any chance you'll give in. You must show more resolve than she does! send the message that bedtime is non-negotiable. No matter how many times she climbs out of bed, repeat the mantra: "i love you. Now, go back to bed." then completely ignore...Until she goes. Then shower with praise!