How can you get a free membership on Moshi Monsters?

There is a Basic Membership for Moshi Monsters which is free, but you will not be able to do all the activities or catch all the Moshlings.

Go to MoshiMonsters.com and click on the Membership icon and then click on the Word 'here' in the sentence "The basic version of Moshi Monsters is free (sign-up here) but Members get exclusive access to all sorts of cool extras." or click on the "Get a Monster Now".