I hate to go against the grain, but I find using foundation sponges wastes foundation. You can also spread bacteria around your face. The heat from using your fingers aids blending. A lot of makeup artists don't bother with sponges.
My tips would probably be:
-Don't be a 'makeup snob.' If you looked inside the makeup bag of a top makeup artist, you would find a mixture of highstreet and upmarket brands.
-Invest in a great foundation if you wear it. It's the one product which is worth spending more on. I would recommend mineral foundation. Spend the least on mascara and lipglosses.
-With regards mascara, the shape of the brush is more important than the formulation.
-Don't wear waterproof mascara everyday. It holds a curl for longer,but it's not good for your eyelashes.
-Metal eyelash curlers are generally more effective than plastic ones. I found some great ones in Tescos.
-Wear a moisturiser with a high SPF.
- The cleanse/tone/moisturise adage really doesn't apply to everyone. I consider toner a superfluous product in general actually.
I could honestly go on forever.

I am so obsessed with makeup.
In answer to a poster's question- the best undereye concealer is a liquid 'light-reflecting' one. Do not use stick concealer under the eyes!!! You will drag the delicate skin. You will still need a stick concealer, ( or a pencil concealer if you can hunt one down,) for spots because light-reflecting concealer actually makes blemishes look bigger.
The best undereye concealer is Yves Saint Laurent 'Touche Eclat.' It's super pricey, but worth it. If you can't afford it, I'd recommend the Boujoirs one. It's about 7 quid.