All you need to do is close AceMoney, exit AceMoney Reminder (right click at the green icon in the right bottom corner of the screen and select Exit) and install a new version over the existing version. All new versions are compatible with data files produced by the old versions. Please, backup your data before performing the upgrade for your safety.
See this video - http://youtu.be/Qtox4cC_hE8
The latest version is always available on our download page
http://www.mechcad.net/products/acemoney/download.shtml
When on the page, click on Download to get the setup file.