Within the great ocean of forum posts there are very complete guides to understand the game. However, I will make a post in a slightly different way, in my style.
First of all you have to understand that this game is quite complex (even if it doesn't seem so). Many come believing that they will play an arcade game and it's not like that... Hey! If you're new to the game and you came looking for that here, let me tell you that you won't find it here, because here if you don't put to work the brain mass I assure you that you'll get to old trying to win a championship. The game is about analysis, understanding, common sense and above all patience. If you want to win your first race in the game, miracles exist, but here they are not very common.
Well, that's what we came here for. Something fundamental in any team is the economic part and unless you have Lawrence Stroll investing in your team, it's better that you avoid to make unnecessary expenses, because you'll need money to develop the headquarter and to survive in the game. The best way to start is to work with the pilots who give the game by default because they get paid very little, although if you start with a pilot over 30 years is better to go looking for replacement, because the older the training will be slower. In that case it would be better to look at what's on the market. You sell the old one and keep the new one. Be careful to always be aware of selling the pilot or staff you do not need, because sometimes we forget to sell or auction and that additional staff continues to charge us salaries which obviously affects the economy. Personally I recommend to avoid buying staff every time you raise the level, because while it is true that the staff is better to have 5 or 4 ½ stars, when you start you raise the level easy and the staff will become obsolete quickly. Keep in mind that if your pilots are in red stars the doctor is not necessary, therefore you can let their contract expire, the game will give you one by default that will only charge you 50K and save you a lot of money. Now, if you want to always be at the forefront, don't pay any attention to what I tell you and update personnel at all times, at your own risk. Try to develop as soon as you can the academy of pilots, so you hire quarry pilots and avoid paying very high salaries of what you buy in the market.
As for the sponsors (which you select in the Finance option) in particular I recommend in principle to use Thomas Hillfinger as main sponsor and WTF1 as secondary, that way you will earn more money by meeting objectives and if you don't meet them, at least the loss will be better. When you are at a level higher than 12 and you have academy pilots that save you salaries it is better to have as main sponsor Red Balls and secondary WTF1. Remember that the secondary sponsor must always be WTF1, in such a case, only the main sponsor changes.
All the above will help you to have a good economy that allows you to develop the headquarter constantly without the karma of having to wait to have money to develop it. After reading this it is strictly forbidden to have funds below 10M and even worse, to reach the dreaded red numbers.
This story will continue...
(best token + bonus available) and for the second one, it doesn't necessary have to be WTF1 
, because iGP objectives will fit to the current team capabilities, so it's possible to choose a sponsor with higher bonus.
