Go up to the nearest lady and just say:
Mira pendeja, te meto el pito si me das dinero. Si no, chinga tu madre putiada! Si quieres ver la verga la saco para acabar con estas estupideces!
Or you can simply say,
Aqui yo mando, o te mando a la chingada. Aqui tienes un hombre echo y derecho con verga de canon. Si no te gusta, esta la puerta de un lado, vete al diablo!
It roughly translates to can you please teach me some Spanish. I cant really pay that much but Ill forever be in your debt. I just really need a little Spanish knowledge to finish this important task I have coming up.