I'll be blunt but honest... you can't... =/
At least not from your end or from ArmorGames' end. This is a server problem at the end of the game developers. All you can do is switch browsers, wait and retry.
To make sure, I tried loading the game and first got this message:
Either there is a temporary network outage or the server is not yet fully operational. Please wait a moment before reconnecting.
I waited a few minutes, then reconnected and I was able to logon to the server and the game loaded normally again. Hope it works for you too! =)