Using the crazy shell stitch, (or any other stitch that you like and have mastered), how about making up a "practice" scarf, of if you have some COTTON yarn, a small dishcloth as your first project? For these items, all you have to do is to make a square or rectangle, stopping when you find the size to be about right.
At first, almost all beginner crocheters find that their work edges are uneven - wider in some areas and narrower in others. You may even find some other inconsistencies of which there seems no explanation. I found a great site that covers most of the common mistakes that can lead to a less than perfect finished product. As you practice, you will find that your work is increasingly even and smooth if you use the following tips. Remember to count the stitches in every row periodically to see if you are maintaining the required number of stitches. One of the reasons I like crochet is that it's easy to rip out and start again, and you never have to worry about picking up dropped stitches, as in knitting.
As taken from:
Edge of foundation row puckers
If the foundation row is tight, the crocheted fabric may pucker. A tight foundation row in a hemline and sleeve makes edges that are tight and uncomfortable. To avoid this problem, crochet experts suggest using a larger size hook and then switching to the recommended hook size. Chaining very loosely will also solve the problem.
Extra stitches - where did they come from?
Most errors occur at the beginning and end of a row. Check the directions. For single crochet, work the first stitch in the row in the first stitch of the row below. Work the last stitch in the last stitch of the single crochet in the row below. For double crochet, work the first stitch in the second stitch of the row below. Work the last stitch in the turn chain. At the end of each row count stitches to be sure it is the number required.
Extra stitches can result when two stitches are made in one, which is particularly easy to do with textured yarns because it is harder to see the actual stitch.
Missing some stitches - where did they go?
If your crocheting keeps getting narrower, it means you are not crocheting into every stitch in a row. Remember, for single crochet, work the first stitch in the row in the first stitch of the row below. Work the last stitch in the last stitch of the single crochet in the row below. For double crochet, work the first stitch in the second stitch of the row below. Work the last stitch in the turn chain. Count stitches frequently.
It is also easy to miss a stitch within a row, especially when using a textured yarn where it is harder to see the actual stitch.
Usually crooked edges are the result of adding extra or skipping stitches. Most frequently, this happens at the end of a row, which is why it's helpful to regularly count your stitches.
If you find you have added or subtracted a stitch try to go back and see where you made the mistake. If it's in the row you are crocheting, simply rip back and correct it. If it was made several rows below, then you have to make a choice-rip back to the point, add or subtract a stitch on the current row or if it is not critical to the design of your project, just continue.
Working single crochet around the edge of a finished garment gives a smooth look.
Tomorrow - learning to decrease and increase...