Once you have the cross solved, the next step is to solve the First Two Layers (F2L). There are four corners and edges above them on the yellow side that are not solved. Since the cross is solved already we are gonna put the cross on the D or bottom face and work on getting the corners and edges. This involves pairing up the corner and the edge so that they become a 2x1 block where you can insert it into the corner slot. Once all four are done, then the bottom two layers are done. Here are some F2L cases.