I find about three minutes is sufficient. A big, soft blush brush is ideal for dusting off excess powder. I don't recommend a lot of heavy corrective makeup to change the shape of your face. There are a lot of books available to help you decide if you are oval, square or heart shaped. I think it's more important to create a feminine version of whatever shape you happen to be.
Some men have a definitely square jawbone.
Trying to minimise it with makeup is risky. You may inadvertently emphasise your five o'clock shadow. A soft hairstyle is probably a safer way to underplay the jawbone. A strong or prominent nose is another trouble spot. In general, don't use corrective makeup on your nose.