How do you get one layer to overlap the other layers?

I've got PhotoShop 6, and I'm trying to make a picture using combined photos. But when I try to combining all the photos, the one I want to overlap all of them is in the very back. So how do you get the layer you want to overlap the rest on top on PhotoShop?How do you get one layer to overlap the other layers?
If these pictures are in the same layer, you can right click on any picture and then click arrange. You shoul have 4 options under the arrange button. Send backward, send forward, send to back, and send to front. If you're trying to bring the picture to the very top then you will click send to front.





If these pictures are on different layers, then you click click window then hit layers, in the layer window you can click and drag layers to any order you want. You may have to unlock the layers to be able to move them around.How do you get one layer to overlap the other layers?
go to the layer window and drag the layers into the order that you want them to appear.

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