It is important to note that every woman's body is different and hence, what works for one woman may not necessarily work for another.
The following guidelines are very basic and may or may not be suitable for you. Consult your doctor, if in doubt.
One last thing - remember to start folic acid as soon as you come off all forms of contraception.
Condom: You can stop using a condom and start trying to conceive straightaway.
Diaphragm:Working on the same principle as a condom, it is safe to conceive after removing it.
Pill: It is advised to wait for three normal menstrual cycles before you start trying. This helps to flush out the synthetic hormones from the body. Also, it helps to date your pregnancy accurately. Use a condom or diaphragm in the meantime.
Coil: Get the coil removed and you can start trying straightaway.
Injection: Wait for three normal menstrual cycles before trying. Use condom or diaphragm in the meantime.
Spermicides: You can stop using spermicides and start trying to conceive straightaway.