Pinstripe suits have been a classic look for many years; however, deciding what to wear with the suit tends to change with the fashion trends. Classically, a solid shirt and slightly patterned or brightly coloured, solid tie does the trick. For a more modern look, more patterns can be mixed, including a striped shirt, as long as the stripes vary in weight from the stripes on your suit. Here's how to pull off a couple of different types of shirts with pinstripes.
If you choose to wear a pinstripe suit with a solid shirt, you will keep the stripe in the suit as the main pattern in your ensemble. This is a good choice, especially if you are planning to wear a tie with any kind of pattern on it. If your suit is dark, a light, solid colour will work well, such as stark white or light grey. If the suit is lighter, try a bright solid colour, such as crimson or bright blue. You could also try to match your shirt to the colour of the stripe in your suit for a polished look.
If you choose to wear a patterned shirt with your pinstripe suit, you'll need to be a little bit more careful with the rest of your ensemble. Classically it was a faux pas to wear two striped clothing items together, but for a more modern look, many men are finding that a striped shirt under a striped suit can work just fine. If you choose to mix stripes, make sure that the stripes are very different from each other. For example, if the stripes in your suit are very light in weight, pick a shirt with large, heavy stripes, and vice versa. The stripes should also be going in different directions. In this case, it is best to not wear a patterned tie. Usually the rule of thumb is that two out of three pieces can have stripes, and only if they differ enough. Keep the third piece solid or extremely mellow in pattern.
If you choose a patterned shirt that is not striped, be sure that the pattern is mellow enough to not interfere with the stripes. For instance, if you choose checks as a pattern, make sure they are small enough so they don't compete with the stripes. However, if your suit stripes are light enough, then a boldly patterned shirt might go very well with the suit; just keep the tie subtle, and always make sure the colours involved in all of the patterns work well together.