I recently purchased nars' casino bronzer and their bronzing brush as well.

I have olive skin and tan regularly.
I never wear foundation or blush.

can someone tell me step by step(how much to put on brush, blow or tap excess off?), simple, and GOOFPROOF way to apply bronzer?

Well...the simpilest way to do it is to just lightly swipe the brush over the bronze, tap off excess and swipe onto forehead, lower cheeckbones, nose, chin and if you like the underchin neck area down across the chest, shoulder blades. As you apply do light circle motions to help it look blended. If you need more reapply lightly.

There is no certain amount just a light swipe of the brush should pick up enough bronzer. If not then do a swirl motion over the bronzer. Sadly, it's all trial and error when it comes to amount that needs to be applied due to different skin tones but just less is more. Also, you can always add more if needed but it's harder to remove extra that you don't need on the face.

Firstly, you shouldn't have to worry too much with the Nars bronzer. I have the Nars Laguna Bronzer and they're pretty much fool-proof. The best, most natural way to apply bronzer is kind of in a "3" shape on your face. So you go in "c" motion from your forehead down to your temples and onto the cheekbones. From there you do another "c" shape from your cheekbones down your jawline to your chin. Then repeat on the other side of your face. Also use a little bit of bronzer over the bridge of your nose. Follow maybe with a little bit of highlighter on the top of your cheekbones and you're set. A makeup artist from Nars showed me this trick and it works every time! It sculpts your face and gives you a very healthy glow. Hope this helped!!