Treating dark spots...

I have dark spots that become visible especially when it gets warmer.It does my head in so much and I have been trying to treat it for ages.I have tried moisturising,concealing,lemon juice and I spotted a fade cream a couple of days ago and I almost bought it but I thought naaaaaa....so I 've been doing some research and I found  a bunch of tips HERE which I plan to try out before I decide to see a dermatologist.But before I do that I decided to ask girls just in case you have some tricks up your sleeve.....?help me out...:)