I Did It Again To My Poor Flowers….

Well I did it again..I do it every summer, I even do it in the fall with mums and other fall flowers. I killed my plants. I swear just when I think I'm doing so good and not over or under watering, they go and die on me. 

I get tips from friends and family on which flowers to buy, which require alot of sun, which require hardly any sun or watering or fuss and I still manage to ruin them. Does anyone truly know how to choose flowers that I absolutely cannot destroy?