Auto body repair & detailing: Blending Paint, foot down, sandpaper

Question
I have replaced a fender on my grandauthers car and repainted it with a flat and clear coat.  I used cans and the color is close but I need to blend into the door and the hood.  How do I do this for the best blend.  

Answer
Stay out of the hood, its too large a panel to paint with cans. Scuff the entire door with a grey scotch brite. DO NOT sand with sandpaper! Now when you color, you only partially color the door. You travel maybe a foot down the door, and at that point, you fan the spray can out and away, in an arc. Stagger where you break it off, as you go down the door horizontally. The next pass, you go a little beyond where you fanned out on the first pass. Use as many coats as it took to color the fender. Then, tack off, and clear coat the entire panel. Simple as that! Bill