IN ORDER TO
Para can come before an infinitive that explains the purpose of the main verb:
In many cases this would answer the question "What did you do it for?"
eg. I went to the bank in order to take out some money.
In English the "para" would be translated as "to, in order to, so as to, in order not to, so as not to.
Fui al banco para sacar dinero
I went to the bank to take out some money.
está ahorrando para comprarse una casa
he is saving in order to buy a house.
Tienes que abrir el sobre con cuidado para no romper el cheque.
You have to open the envelope carefully so as not to damage the cheque.
Para is used for purpose. In these cases "para" would be translated as "for, for the purpose of, intended for, or on behalf of"
Compré una mesa para el salón
I bought a table for the living room. (intended for)
¿para qué lo quieres?
What do you want it for? (for what purpose do you want it)
FOR LENGTH OF TIME
Necesito una habitación para 6 noches
I need a room for 6 nights
IN TIME PHRASES TO SPECIFY A FUTURE MOMENT IN TIME
lo necesito para mañana
I need it by tomorrow
tiene que estar listo para el día 16
it have to be ready by the 15th
Es alto para su edad
he is tall for his age
TO BE ABOUT TO (note in South American they also use por)
Está para llover
It is about to rain