So I've heard that hosting events is a great way to earn money for your band. But when I hosted "Redwood: Competition #1 (Redwood, MS)", [Which is still on by the way until Nov 29th] I spent $1,500 to host it, and only got $400 in return. That is literally a profit of -$1,100. Any tips on how I can do a better job in the future?

I do understand that you got a late start this season, so this is advice for future seasons.
A great way to make money is to have it up early in the season, as in very shortly after the season resets. That way you'll have a lot of groups apply. Scheduling is a big part of it. As your time on the circuit progresses, you'll start to get an idea of what days leagues for certain disciplines have events. Try to avoid those days if you can.

Start small. You have a five group competition, which is a good start. Keep ticket prices kind of low for now, but high enough that you don't have to sell out to make profit.

The game guide has some great bits for hosting, because it really is a great way to earn money. My drum corps made $43100 this season from hosting.

It takes time to perfect hosting, but it helps your groups out when done correctly.

Also, in the future, schedule your events first, before you spend money on staff. Shows will be your biggest source of revenue, so it's important to make sure you host them before doing anything else. As for this season, you still should be able to make a profit, you still have 3 or so days for tickets to sell