There are many methods for contraception but commonly used are Oral contraceptive pills, Intra uterine devices, Vaginal ring, Condom, Contraceptive injection, Contraceptive implant.
Oral contraceptive pills are of many types, all having hormones. Most effective are the combination pills with low dose hormones. The low dose ensures less side effects and the combination of hormones ensures regular menses and less chances of inter menstrual irregular bleeding or spotting per vaginum. These pills can be taken for many months/years. But it is better to start these after visiting a gynaecologist. One caution! Smoking and oral contraceptive pills is a very bad combination!!
The safer contraceptive with very very less failure rate are the various intra-uterine devices. There are two type of these devices; copper and hormonal. These have to be inserted in the uterus by a gynaecologist as a OPD procedure. Of these the hormonal ones are better, available by the name of Mirena which can be used for five years and then replaced with a new one. The copper devices are of two types which have to be replaced after every three or five years depending on the one used.
Then there are hormone loaded rings which are placed in the vagina every month and the lady can insert it on her own every time. This is also a safe contraceptive method with less failure rate. Only issue is using a new one every month.
Injectable contraceptives are also available with an efficacy of three months. This is also a very effective method but sometimes there is a side effect leading to irregular bleeding in those three months.
Very commonly used method is the barrier method where the male partner uses condoms. But this has the highest failure rate.