how can I make ttc fun?

Me and my fiancé have been ttc for 3 months, at the beginning it was fun but now we just does it because we 'need' to. I used to be fun like before we was ttc. Any ideas how I can make sessions last longer and more fun, as now it seems like a chore. I try to take things slow and do different things and ask him what he would want/want to do, and he just wants to have sex and fall asleep.? I don't think I'm being selfish wanting this time to be fun as when/if we have a baby everything will change.