Paste a Photo Inside a Selection
Open the picture of the daisy below in Photoshop:

Next open the photo that you want to use to insert into the flower above. I used this cute baby photo I found online.

Now you just want to use the head part of the photo, getting rid of the background and shoulders. Select the Magnetic Lasso Tool:

Zoom in on the photo using the magnification tool
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Click around the baby's head to select it. When you are done your selection should look like the photo below. If you make a mistake, simply click the delete button to deselect your last selection:

Now click Ctrl + C to copy the selection to the clipboard. Click on the flower picture and select the ellipse marquee tool:

Click in the center of the flower and with the Alt key depressed pull out from the center to create a selection. FYI: You can press the spacebar key to move the selection while sizing your selection.

Then select Edit > Paste Special > Paste Into:

How cute is this?
