[samokan]

nope.. wearing white is a no-no on a japanese weddings.. because the bride is already wearing it.. I wore black on my friends weddings.,.

as for gifts, its usually money from 30,000 - up. The amount should be odd and the money should be new. Go to the bank and exchange some notes/bill and tell them its for wedding, they will know what to do, and you will notice that even the serial numbers on the notes are sequential.

then put the money in a wedding envelope, you can buy them at convenience or even in 100yen shop. Each envelope has specific amount on them, be sure to the one that specify the amount you will put.