Can anyone give me effective fundraising tips in FMA, as I try to squeeze FMA in during the busy times of my university life to be better prepared when I'm not busy and I'm trying to push for a medal?

Also, do I need to continually rehearse in order to get fundraising?

put fundraising on your highest level--even if you didn't practice once all day, you would still get the fundraising benefit. Obviously hosting larger events with the most influential groups is the easiest way to raise money. Many in the past have "taken a season or two off" to focus on fundraising and then come back strong when ready.

^
ive taken like 5 or 6 seasons off and gained a lot