superimpose is needed.
okay, so here's an example of a photostring cover;
first find a string or simply use this;
next, simply pick the magic wand tool and tap on the parts that are not needed. Next, put pictures of the person you want on the cover, you can either follow my style, which is covering the Polaroid frames, or you could put the picture inside the Polaroid, up to you. Next put a PNG of your choice and add your font on Phonto.
Fonts;