Build stadium, make sure that the estimate building time is before your next home match. Invest as much as possible in stadium.
Invest 20k in the draft every week.
Start training 18,19 years old with at least all-star potential.
adjust ticket prices as soon as neccessary try to sell 90% of your seats.
save money, save money.
You need at least 4 seasons before your stadium is big enough to get in II or even league I.
Don't rush, don't buy big salary players.
Only in the dark, we succeed!