Just put it on my bed. This is the first night for it. Im hot natured and so far I have remained very very comfortable. I sleep on my back and side at night and so far it feels great. If things would change I will post an update.   
Update.... Ive had it on for 2 weeks and I ABSOLUTELY LOVE it. I can already see a difference in when I get up in the mornings. I have almost no pain. And I believe that that will go away soon. I ONLY problem that I have,is that the topper shifts off the bed. But that will be an easy fix. I will be getting a set of sheet suspenders to hold it in position. Then my issue is solved. If and when I need to replace the topper I WILL buy from them again.