My mom used to get me mascara sampler sets every year from Shoppers Drug Mart here in Canada. It had their higher end mascaras in it, and a coupon to get a full size one of whatever one I liked best. I’m not sure if Sephora does something similar but I loved it because it gave me the chance to try a bunch of different ones.
I use Maybelline Strobing Light stick, I rub a brush on the stick and apply it to my cheekbones, bridge of nose and tip of nose, very top of my cupids bow. I like a stick over a powder because it melds into my skin right away and looks more natural on me. If it’s a special occasion I’ll just apply a bit more of it, and I’ll add some under the arch of my brows and the inner corner of my eyes to amp up my eye makeup a bit. Basically the high points of the face that naturally catch light that you want to draw more attention to.