Try to have goals for how long you want to manual. Start really small and have a friend confirm that you manual to that distance. The more you do that the more you'll get your manuals down.

Man just go fast and balance your body. Swing your arms like a crazy monkey and then you can do it

When you wanna trick out of a manual first put the front wheels close to the ground, but not on it, then snap the tail (or flick it) then slide your foot (or heel) on (or off) the board ☺

You should always try maybe pop shuvit out or Ollie to rail it is really simple and easy

Shuvits

I don't skateboard at whole lot but if you try to keep your center of balance right above and in-line with the back truck you should be set

Lean to drop off a curb... Just do the same thing

For those tricks it helps to get your back foot on the toes doing manual, and do the pop using the ankle move to snap down.