One of the best ways to practice machine quilting is to make small quilts. I just finished a receiving blanket, and it was a quick project but lots of fun.
It's hard to see in the picture, but there is a yellow duck sewn on each of the striped blocks. To do this I used a method I learned in the book Show Me How to Plan My Quilting by Kathy Sandbach. I went on line and found a coloring page for a rubber duck (http://dulemba.com/BOOKS/Soap/Activities/CP-Duck-big.jpg) and traced it on a piece of freezer paper. I ironed it to the block and then stitched around it. I removed the freezer paper to do the wings, beak, and eyes. I sewed around the portions of the design three times to give it some 'oomph', and I didn't worry too much about tracing my stitching lines perfectly. I love the little ducks!
For the rest of the quilt I used a pebble, or circle, filler to mimic soap bubbles. Around the edge I quilted waves in the border.
As I quilted this receiving blanket I had a lot of fun NOT obsessing about perfection. I realized that I have finally achieved a rhythm to my quilting and that I am doing a pretty good job of keeping my stitch size regulated. I still had some unintended wildness as I tried to trace over my circles, so thank goodness this is a forgiving pattern. But I'm happy to be in a place where I am more concerned about relaxing and enjoying the process than being perfect. That, too, will come with time.