If you put a channel in the foot end of the top sheet and slip a piece of PVC pipe in it shove that down between the mattress and the wall the top sheet stays nice. I have to have a straight top sheet LOL
Also it makes it very easy to get the top sheet on the bed.
I have a post on my blog about it with pictures
here
Liz
2008 189FBR & 2014 FORD F150
137 Nights Camping this year
Tons of Free or Inexpensive Mods WackyPup.Blogspot.com