Welcome to INC!
So glad you decided to join us.

Here are some ideas in what to do the first week in joining:

Register on the guild fourms found here:
http://incperenoldeguild.freeforums.org/

Then make a post to introduce yourself! 
We love to hear about you and why you decided to join us. 
:)

 Complete an application to gain raiding status.
If you're looking to raid you need to fill out an application on the forums.
Doing so ASAP will get you into the up-coming runs faster and gear will start floating your way.

Get involved on the runs.
If people are looking for heroics, don't be afraid to speak up and tag along.
If there is enough interest you never know what will happen.

Join battleground PvP groups.
Even if you're not a huge fan of PvP it can be a great and relaxing way to get to know your new guildies.