Help Please

I looked on here for info so sorry if this has been posted.

I am trying ad more songs to my touch. I already have music on there. The problem I am having is everytime
I ad music it takes off the music I already had on there?

How do I just ad more music and Keep what I have on there. I am using windows Vista. with all updats with itunes.

Thanks in advance for your help. Happy Holidays to all.

JOHN.

 

What is does it when I want to ad new songs on the touch.
I clears out all my music and puts on what I am adding new to it. I have to then re-load all my music again. I am sure it is an easy fix and I am just not doing it rite. Thanks for your time Happy holidays.