The beginning is simple, you just download the latest version of Firefox, Opera and Internet Explorer. But once you have these three installed you still have two to go, which isn’t as simple as it seems.

For Firefox you can simply get the Firefox Portable version, which can be found here (if that links stops working you can go directly to the project following this link)
Once you have unpacked the file you can then navigate to the map, and open the FirefoxPortable file (make sure you don’t have 2.x open tho)

Internet Explorer is a different story. Once you have installed Internet Explorer you’ll have to search for a Internet Explorer “portable” version. Thanks to the people at evolt.org there is an Internet Explorer 6 standalone version.

The downside to this is that (unlike with the Firefox portable version) the system still thinks the browser is Internet Explorer 7, so if you are using Conditional comments you’ll temporarly have to change the comment to Internet Explorer 7 instead of 6.

I hope this is useful to some of you, seeing how web design can already be a nightmare with all the different browsers (more specific, the mess that is called IE ;))