It all depends on your baby. You can try tummy time. But my son wasn't even early and he didn't crawl till around 9-10 months and didn't walk until 14 months.
My son was 5wks early and he didn't crawl until almost 9mths, dr said it was in the normal range. He's now 13mths and can stand by himself for a couple of seconds but not walking yet. It really is in their own time, just provide opportunities for them to practice their skills if they want to.
O and make sure he is getting plenty of tummy time. We used toys to try to get him to at least pull himself forward. It took a while but they will do it when they are ready :)
My son was 5 weeks early he crawled at 8 1/2 months and didn't walk until 15 months