Today's technique is super easy but does require the right stamp set (or some great creative skills on your part). Two step stampin is simply laying 2 stamps on top of each other to create a two tone (or 3... why not?) image.
Here's what I used and did.
The Hearts a flutter stamp set was perfect for this project as it has a great full heart shaped stamp which I used to create my base image in a pale colour, and 3 different patterned heart stamps (the same size) for me to use in the second step - laying my stamped images. Stampin' Up has some great stamp sets created especially for this technique but you can also use 2 different stamps that contrast. Try keeping one image a block image of a solid shape and layering that with a sentiment stamp or an outline stamp that you might ordinarily use for water colouring. There are no rules so let your imagination run wild.
If you're not confident to make up your own layering why not grab a set like this. It's perfect to get your started.