help with sleep

Anyone that has their baby on a schedule please tell me how you did it and what the schedule is like? My baby girl is four months old and literally only naps for 30 minutes spurts. I try to put her down for a nap after an hour and a half of being awake each time but with a 30 minute naps and taking 20 minutes to fall asleep I get nothing else done all day. She sleeps well at night and only the daytime naps are an issue.