Newbies,
Mongering is like a box of choc... damn that's so overused.
Try a little of everything on the plate. What do you have to lose? Better to pick the hottest Colombiana you can find at the BM & get your brains ph&*#d out, than spend $80 on a gringa movie/dinner date.
Enjoy her body, massage her, tell her to massage you, enjoy the BJ, be creative. Most likely, if you can (or if she let's you**) see if you can make it past 20 minutes of hard ph&%king and let that image of her beautiful face and rack be seared on that DVD in your permanent memory. Speed up, slow down, make her work for it. Be certain: she will grab hold, not let go, and make you go "POP."
Worst case, you will know better the next time. The only guarantee in life is that they always ask for cien.
Betty Crocker said you got to break some huevos to bake a cake.
** footnote: practice makes perfect, they get more practice than you on busting a nut