Lube???

So people have suggested lube to help with getting wet. I’ve never used it! My question is when do you use it? Before/after foreplay? Straight away? Just before having sex? Do you girls just put it on yourself or do you put it on your partner as well? And also what’s the best way to suggest using it to my partner? Do I just tell him I want to try it? I don’t want him thinking I can’t just get wet off foreplay? I’ve never used it I’m so new to this ahaha any help would be great’ x