I wish I'd known that this job was feast or famine!
When I first started out about 14 years ago I blew my money on having fun: trips to Rome, Prague, and Boston. Shopping, drinking champagne because the Weakest Link was on! (I'm such a weirdo.) It was fun though. Life seemed like a never ending party.
Then I got older and the quiet times came. There were months when I didn't earn anything and I ate beans on toast while wondering how I was going to pay the rent.
If I could talk to my younger self I would tell her to put away 30% of all earnings after tax. Save up for that rainy day because it will come unless you keep on top of the marketing and tweak it as you (and your body) change.