Summarize the following:
When you forget a pill, take the pill as soon as you remember and take the next pill at the regular time. Certain combination pills, especially multiphasic pills, may have additional instructions that you should follow.  For most pills, if you don’t remember until the next day, you should take two pills on that day.  If you forget your pill for two days, take two pills on the first day you remember and two pills on the next day.  If you forget a pill at any time during your cycle, you should use a backup form of contraception (such as condoms) until you finish the pill pack. If you forgot a pill during the first week of a pack, you may need to use emergency contraception to prevent pregnancy. If you take progestin-only pills (instead of the more common combination pill), it is extremely important to take it at the same time every day. Even a few hours off can allow you to become pregnant. If you are not sure what to do if you have missed a pill, or if you want to know whether you need to consider emergency contraception, contact your doctor. Tell them exactly what happened (how many pills you forgot, for how many days, etc.). How you treat missing or forgetting a pill varies depending on the pill you’re taking, so contacting your doctor is always a good idea. Use another method of birth control if you are sick and experiencing vomiting or diarrhea because the pill may not stay in your digestive tract long enough to be effective.  If you vomit or have diarrhea within four hours of taking a pill, it is likely to be ineffective at protecting from pregnancy. Use a backup form of birth control just as you would for a missed pill. If you suffer from an eating disorder and use vomiting or laxatives, an oral contraceptive is unlikely to be effective. Use a backup form of contraception. Consult with your doctor or a mental health professional for help.

Summary:
Try not to ever miss pills, but compensate if you do. Contact your doctor. Consider alternative options when you're sick.