A good place to start is by reading this:
(144856.1)It's a very good idea to hold off on spending your money before you spend it on the wrong thing. Probably the best advice is to scout out your competition and see how good they are. There is no need spending 250k on a roster when a 150k roster will have you comfortably win.
Personally, I'd hold off on buying much at all until you learn more about what to do. Losing a few games at the start of the season won't do much for you in the long run, but blowing a lot of cash can take a while to get back.
In fact, there is one thing you can do right now. You don't need 18 players on your roster. So I'd get rid of...
(24686478)(24686471)(24686483)(24686476)(24686479)(24686480)(24686481)I wouldn't even worry about trying to sell them. Just fire them. There'll be more you'll fire/sell, too, but that's a start.