You should have a good base tan in 8-10 tanning sessions then one to three tanning sessions a week should maintain your tan. Don't try to rush your tan. A tan should be obtained gradually. Gradually increase your exposure times. Consult your physician if you are taking any medication.
Some medication can cause extra sensitivity to the UV light, causing overexposure.
Also consult your physician If you have any type of skin irritation or other condition. Always wear protective eyewear. Ultraviolet light will penetrate the eyelids. Some skin types tan quickly and easily while others just don't have the pigmentation necessary to develop much of a tan. It's recommended that you not tan at all.