It's not possible to start the game from scratch once you've started, however if you've made some mistakes in the early game here's a few tips to get you back in the action:

* Make sure you play through the campaign mode and replay matches so you can claim all Cash, Gold, RQ and Cars from each prize board

* Enter the multiplayer events - most have a decent range of prizes so even if you don't make a high position you'll still win something!

* Sell the cars you don't need for cash, but be careful not to scrap your Rare or better cars!

* Use the Free Gold option, the more you watch the more you get.

* A lot of packs are available for Cash, so you should be able to to find one to suit your budget!