Welcome Daniel to the forums,
It is typical of us males to go for the most sexual product we can find but as monesmademedoit said they are very situation specific. Also at 19 you have have to be careful with none heavy products as you are producing a lot at your age and you carry a strong risk of ODing and getting negative reactions (the opposite of what you are trying to achieve)
AMMO is great as is Instant Shine although they have different effects.
with Respects to usage tips you will need to find your sweetspot ie the ideal dosage for you. check out the link below.