Dont get ahead of youself. Does he sit and laydown for treats, or because you are asking him? Will he sit and lay down wihtout treats and using praise for the reward? Will he sit and lay down on a walk, with distractions like other dogs around him?
If not, you need to master all of these things before moving on. Sit and lay down aren't tricks, they're vital commands. If he wont respond to them under chaotic, exciting, or distracting circumstances without treats, then those commands are unless.
If he takes off after a squirrel running across the road, you need to be able to yell, "stop! Sit" and have him listen, or he could get hit by a car.