Because Em wanted a bit more about clear stamps (and because I'm more than happy to talk about them), here's a little bit more about clear stamps.
Clear stamps come in two parts - the stamp itself and the clear acrylic board that you place it on to use the stamp. There are endless possibilities when it comes to the stamps. I should know it took me hours to choose the ones I did. I ended up with a set of letters and journaling boxes (artful boxes with "lines" for writing). I also bought a set of acrylic boards with 3. I especially picked out these boards because they had a grid on them making it easier to position my stamps straight. In the short time that I've been using these I've found the 3"x3" one and the 2"x7" one the most useful. Maybe if I had multiples of the letters I would get more use out of the big block, but having only one of each letter requires a little creativity and making use of the best characteristic of clear stamps... they're CLEAR!
How they work:
1.) Pull stamp up from clear plastic sheet and apply to acrylic board. The stamp will stick to the board - pretty nifty. Prior to pealing the stamp up from the plastic it's stored on I like to gage my positioning. This can be done once on the acrylic board as well. The clearness factor really helps with planning and getting the stamp in the right spot. With regular stamps I was always giving the placement my best guess, but often it would come out wonky.
2.) Next you'll want to ink your stamp. I have been using an ink pad to do this which works fine. But I haven't been very satisfied with the quality of the ink pad I choose. I believe you can ink your stamps with paints or liquid inking methods, but I don't have any experience with other options. Maybe I should look into that. I simply place my stamp firmly on the ink pad a few times since the pad usually isn't big enough to ink the entire stamp at one time. Another advantage to the clearness is checking how well it was inked (but this could be done by just turning the stamp over too).
3.) Look through the clear acrylic board, position your stamp and press down firmly. This step might take a little trial and error as the quality of the stamped image depends on the amount of ink on your stamp, the quality of that ink on the stamp, and the distribution of the pressure you apply. I've found though that even when it doesn't come out perfectly, I love the look I get with stamps.
Now go stamp and get creative. Another advantage of clear stamps is that you can combine many at one time. So, spell words out and such. Have fun!!
*a note: the links to the letters and acrylic boards are just to show you what I use. I don't know anything about the sellers offering these products. As always, if you purchase things online make sure you do it through a reputable seller.