Hi, Chiva... and welcome.
I glue my linoleum to pieces of plywood using something called Gorilla Glue
. I like it better than Elmer's white glue or wood glue because it sets up fairly fast. I don't glue until I have my finished linocut because sometimes I reduce my linocut size and want to have the lino just a tad bit smaller than the wood.
The advantage of mounted lino is that it is easier to ink and print because it is more solidly even all across the surface. There is no curling or waviness that can happen sometimes if the back surface of the lino gets wet. Also, if you have cut a lot of your lino, the cut area is very thin and the wood firms up the entire area.
When I glue, I make sure there is no glue coming out the edges. Also, after applying the glue and adjusting it onto the wood, I turn it face down on a clean surface and use something heavy on top of it all until the glue is dry. My husband's hand weights or the dictionary are good for that.
Hope that helps some...