How can I make a sticky note stay open?

I'm using Acrobat X Pro on a large screen under 64-bit Windows 7 to read PDF scientific journal articles.  I regularly add highlighting (with comments) and sticky notes.  I would like the sticky notes to stay open because my screen has lots of room to display them.  Although sometimes I can get sticky notes to stay open, more often than not they close.  What steps can I take to make a sticky note stay open?

Thanks for your help,

Don Macnaughton