How can I get my baby to nap?

My baby is 3 months old and sleeps great through the night. Sometimes wakes for a feed part way through but often sleeps straight through. She rarely naps during the day, maybe a couple 20-30 naps if I'm lucky. I have tried taking her into her room, making sure it's quiet, lights out with a bottle and rocking her but no luck. Any tips?! Some days are a real struggle to get anything done!