how do I configure it

Setting up Time Capsule for the first time

Much of the info on that help doco is hopelessly out of date.. like using 5.3 utility is rubbish..

Use AirPort Utility 5.3 or later, included with the Time Capsule or available via Apple Software Updates or from Apple Support Downloads, to set up your Time Capsule.

Complete balderdash.. no new Airport AE or TC will be setup properly using a v5 utility .. it needs later v6 utility. And it doesn't come with the TC on included CD-ROM .. it is built into the OS.

If you run into issues just ask.. I am sure we can provide up to date info.. which it seems apple is incapable of.. even though that info was updated last month.. amazing eh!

We do need full details of your network and how you want to use the TC in it.