There are at least three ways that I know of that you can transport a variant for a program.
When you first transport a program, all elements of a program are transported along with the source code. This includes any variants that have been created at this time
After the first time a program has been transported, there are two ways to move a variant. The first method is to manually add an entry to the transport for the variant you want to move. The format of the entry is LIMU VARX xxxxxxxxName_of_the_variant where xxxxxxxx is the program name.
The last method is the easiest, in that you do not have to remember any arcane codes. Go to the ABAP editor, and go to the variant screen. Under the Utilities menu is Transport Variant. This allows you to choose the variants to transport, and the transport to put them in.
Also you can refer: