There are unlimited options for this project (Yay!)
I'll show you how to do the pinked ones I love as they're a bit trickier but you can let your creativity go wild with these!
Materials you need:
Card or Paper
Pinking Shears or Normal Shears
Lay your hair clip on your card or paper abd draw round it leaving about 1/2 cm border all the way round and cut out - This will be your template.
If you are doing a pinked edge design you will need to fold the fabric in half and pin it before drawing round your template so you can get the points in the same place on both sides
However, you iy just want a nice smooth edge you can skip this step and just copy the template onto the felt and cut :)
Again, you only need to complete this step if you want a pinked edge.
Once you've copied your template move the pins to inside the line to hold the pieces together as you cut.
Also check out my awesome air erasable pen! The BEST investment ever!
Cut round your outline with the pinking shears - if in doubt, it's best to cut slightly outside your line.
Unpin the two peices and lay your hair clip on one of them.
Mark where the top of the gaps on your clips are with a dot - It doesn't matter what you use for this as it will be on the inside.
Once you have two dots - Remove the clip and join them up to make a small line.
Make a snip across you line, open your hair clip and slide the smaller back through your slit.
Adjust the hair clip so it's nicely positioned and snap shut.
Now take the other piece and decorate however you want.
This is the bit I normally mess up with so check and double check you are decorating the right side or your pinks won't match up when you join the two pieces together.
Now sew the two pieces together round the clip in the middle.
I've used a simple running stitch but a blanket stitch works really well with a smooth edge.
Now you know how - Go mad!