Start a “Local Game” using the map you are interested in and check out how it works. Everything is done with a mouse. Play around with TripleA and see how it works. To download maps, use this guide from the TripleA War Club: Finding and Installing Maps for TripleA
Start TripleA and download the appropriate maps. Once you download it, clicking the exe file should install it for you. Depending on your system, you usually want to either download tripleA with java or the triplea all platforms zip. Use the latest stable version (as of writing it is 1322). It is available on all modern desktop platforms: Windows, Mac, and Linux. Use this link to download TripleA: TripleA Download. Let’s assume you’ve never played TripleA before. The process of playing-by-forum is nearly identical to playing by email. Playing forum games via TripleA is easy, especially if you’re already familiar with TripleA.