Those are absolutely fantastic. Perfect images for the prints. Did you use a start up kit, or buy the materials from separately? Congrats.
I bought a beginners kit a long time ago. But over the course of the last couple months I had bought some screens and a better squeegee. My friend told me that a lot of the ease in screen printing really has to do with the quality of squeegee you have and that seems to be true.
as far as preparing the screen, it's pretty easy with the photo emulsion. you just have to work a thin layer of it on both sides of the screen. basically just enough of the liquid until the screen in covered.
the images i just manipulated in photoshop. converted them to grayscale, increased the contrast and then converted them to a bitmap. once you do that you get a couple options for output and the chandelier i just did at a 50% threshold. photocopied them onto transparencies and then exposed them on the screen with a regular ole' desk lamp (with a 150W bulb).