McGuire's advice is excellent for new teams.
Keep your doc and PR mgr at level 1, but don't be afraid to hire a level 10 trainer. Don't waste money on the TL, either. Making your trainees better is the way to go. Fill in your non-trainee slots with cheap, decent upgrades after you receive 2 TV game payments.
Slowly increase your stadium. See other threads for how to proceed on that.
Also, check on the level of the player giving advice. By that I mean, Mcquire and I are in DIV. We know what works there. If you are in DIV, you should ignore the advice of players in DI like kkl, above, who is in Singapore DI. His world is vastly different from ours. 40k per week from Merchandise will not happen in DIV under any conditions.