過大禮-嫁妝

I cannot follow. boy side sent me gold accessories during 過大禮. and later my side need to send gold accessories and something to boy side.
The groom's family sent you some gold jewelery, but nowaday they may only send you just a "lai-see" for all the items. As for your parents give you the dowry, and traditionaly those should be sent to the groom's home before wedding, of course it's hard for us live in today's busy life, so some bride will bring them to the groom's home on their wedding days. If you are follow the entire tradition, you will wear those on the groom's family visit on your wedding day, or ask the groom bring them to your house when he pic you up on the wedding day.

the problem is......on big day, i leave home to boy home, i will wear the gold accessories, so the gold accessories is from my side or boy side?
After you are fully dressed, you should wear the jeweleries from the groom's family, you and the groom will present the tea ceremony to your parents and to other relatives, they will give you some jeweleries or lai-see, put the jeweleries at the time you get it.

when arrive boy side, i need to wear the gold accessories from boy side or my side?
Both.

my set from parents are very nice, i think that i should wear it to boy side right? if so, how to get them back. i want to exchange. i want parents to wear the set which they bought for me on my hands..........
The jewerlies are on your bodies, they are yours. Even all the dowry are suppose yours.