Making a quilt out of baby clothes. can i just make squares?

I just made a disney princess small quilt using squares of solid and disney princess. sewed the strips together and then made the border and tacked a back to it. I dont know if this is the proper way to do it but was wondering if i could do the same when using square cut outs of my daughters clothing? They also are not all the same size there are about 4 larger ones then the rest can i use this as a center some how? any answers would be appreciated.