Making Coasters for Christmas Gifts

Since it's almost Thanksgiving, now is the time to start your Christmas DIY gifts.
I just love Pinterest and I have boards there.  http://pinterest.com/pattm60/
Anyway, on Pinterest I saw someone posted making coasters using tiles from Home
Depot or Lowes.  I decided to try it as I am a DIY'er since waaaayyyy back.  If you've ever read my blog you'd already know that.
My hubby was going to Home Depot because we are building porches and getting our new place finished up altho we've been here since the first of July of this year.  I had him pick me up 20 4x4 white tiles (.16 cents each) and a couple cans of sealer.  I already had the Mod Podge and sponge brushes and roller so I was good to go.
I printed out a few photos on matt photo paper to use.  On pinterest the gal used holiday napkins.  Didn't have those so used what I have.
Here are what I've done so far:

the pear ones are my fave so far.  The 3rd photo is of my supplies.
Here's what I've done so far:

1. cleaned off tiles with alcohol
2. brushed mod podge over the blank tiles
3. put picture down on top of wet mod podge
4. smoothed bubbles out of photo (I had to redo a couple of the tiles because the pictures had too many bubbles under them that wouldn't go away.  I just tore the photo off the tile, washed the glue off and dried the tile and reused it.)
5. brushed mod podge on top of photo and let dry over night.
6. I also used some twinkle paint to dot some twinkles on a few places on the snowman and the merry christmas tiles.  still have to do one more xmas tile.
7. today I will spray the dried tiles with the sealer and that will be that. 

I'm going to michael's today to get some think cork board or a similar product to glue on the underside of the tiles so the tiles don't scratch where ever they are put.

Something that I just noticed is this:  if you don't trim the photo so that it's just a tiny bit smaller that the tile all around then the photo will just lift up from tile after it's dried.  I just had to trim some places on a few of the tiles because of this and reapply more mod podge.
I tried to rough the top of the tile up with a large acrylic nail file but it didn't do anything.  So the best thing is to make sure photo or image is smaller than tile so that it will stay glued down.