How to get LO to learn crawling?

I tried tempting my boy to move forward when he was having tummy time by stacking blocks in front of him. he loves to tumble them so he will push himself forward commando style. I slowly increase the distance between him and the stacks of blocks each time so he moves further each time. however, eventually, he got from commando crawling to sitting first before crawling without his tummy touching the floor. you can encourage her to sit up. try putting cushions loosely around her to protect her if she topples over. supervise her as well. after a few weeks, she should be able to put out her hand to keep her balance.