How do you do your base makeup in the summer?

I'm someone who never really cared about base makeup, but my skin is a mess these days... so I've suddenly become interested...

Since I have dehydrated oily skin, it’s a total mess—oily spots and dry spots everywhere. When I use a cushion foundation, the sides of my nose cake up.

Maybe because my forehead is oily, the product really went in there haha. I want to try to achieve a nice skin look...

How should I do my base makeup so that it applies well? Does applying primer cover blackheads well?

I sweat a lot in the summer, so I am curious how everyone does their base makeup.