How to get more sex suggestions?

TTC #1 month 5 - I have a job that requires about 12 hrs a day. My husband has chronic arthritis which can be limiting. We really enjoy getting down. But with his pain and my schedule it was hard to get a session when we were not trying. But now we are trying for every other day (daily around high fertility =BFN for 4 months). My husband still wants to keep it fun and not a chore.

Any suggestions on how to keep it fun and frequent despite pain and schedules?