Time and again, I have friends who told me about those errors that they have made on the course of creating their cross stitch creations. These errors usually result from immediately working on the design even without preparing and conditioning the fabric for use first.
Preparing your fabric is an essential step in cross stitching. Without this step, you may incur errors such as the unraveling of the fabric in the middle of stitching, shrinking of the fabric, running of the dye during the wash, and the like.
The first thing that you have to remember is to pre-wash the fabric before everything else. This is because fabric materials have the tendency to shrink once washed, though most experts agree that when it comes to fabric used for cross stitching, the shrinking may not be that substantial. It's better to be safe than sorry, though. For darker-colored fabrics, pre-washing is even more important to allow the dye to set there. You won't want the dye to run after you stitched unto it. For this, experts also recommend making a mixture of one part vinegar, three parts water. Soak your fabric in this solution for about 15 minutes and run it under cold water after and dry.
After this is the time to use masking tapes to cover the edges of your fabric. This is to prevent the unraveling of the fabric, which was mentioned earlier. This also means that you will have to cut the fabric big enough since you will be also cutting the edges thereafter. If you don't want this kind of solution, you might also want to use a fabric stiffener on the edges or, better yet, make zigzag stitches around the edges of the fabric.
Those steps mentioned above should be able to take care of potential fabric problems. If you encounter other issues not mentioned here, do drop a comment.