It's hard to give advice without knowing the details of your team or what your goals are. If you go to the Canadian forum there is a mentoring thread and you can sign up to have an experienced player who actually knows what s/he's doing provide you with advice.
1. Fire/Sell all players under 3k salary.
2. If you still have more than 10-12 players then fire/sell some more players.
I am not sure about this. In my experience you need around 13 players to properly regulate game shape. (You can probably do it with 12, but 10 makes it really, really difficult)
I know that the 3k cut off is the go to advice on the forums, but I don't think it's particularly good advice for brand new, bottom of the division players. Most likely 2-4 of your players are only going to play in the scrimmage at the end of the week - why bother having guys with $3k-4k salary playing garbage minutes when $1.5k guys can fill in just as well? Money is tight in the bottom divisions and if you can save $5k-10k per week by going cheap with the far end of your bench then you can save up to expand your arena or so something else that's useful.
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Some general thoughts:
In terms of player purchasing and training I would really suggest prioritizing outside defense and inside defense. The more guys with strong+ in those two skills that you have the better you're going to be and the easier it will be to win.
I'd start trying to use TIE whenever possible to build up some higher enthusiasm.
I'd switch up your tactics a bit too, but I think that's not a major priority in the bottom division.
I generally start the best players in both league games (different for my training position) and then the backups usually get back up for two games, starter or backup for a third (depends on how the minutes break down). It's pretty straight forward but gets more difficult to manage when you're in the cup.