How to Get Rid of Black Spots and Blemishes on the Legs?

I want to get rid of black spots and blemishes on my legs. I don't know what to do. I tried with natural ways, Lemon, to fade my blacks spots and blemishes. But it didn't work out. And I've tried with some spa things, exfoliating on my legs..but the black spots and blemishes are still on my legs. I can't even wear short skirts and shorts. I'm really really depressed now. What should I do to get rid all of it? Please help me.