The condom is a rubber sheath that fits over a man's erect penis. In this way, it serves as a barrier, preventing the sperm from entering the uterus. It is 90% effective as a method of birth control. It also offers the best protection against venereal disease, including AIDS. Condoms are available at any chemist. 

The condom should be used every time you have intercourse. There may be some decrease in the sensation during sex. The man should put it on prior to any genital contact. You should avoid the use of oil-based lubricants like petroleum jelly, cold cream or baby oil as these can weaken latex condoms causing them to break. If necessary, use water-soluble lubricants like K-Y Jelly. Some condoms are lubricated with spermicide, which increases their effectiveness. 

Half an inch of the condom should be left at the tip of the penis to collect the semen. The condom must be removed carefully because if the semen spills, it could enter the vagina. Thus, the male partner should grasp the condom firmly at the base after climaxing to prevent it from slipping off and withdraw promptly before he loses his erection.