From Test-Scratch-Wiki

Complete and submit the following form to request a user account.

Make sure that you first read the Wiki guidelines before requesting an account.

Once the account is approved, you will be emailed a notification message and the account will be usable at login.

Please read the guidelines below. If you do not, your request will be rejected without any further thought. We cannot stress enough how important it is to read this completely and thoroughly before requesting an account. This section is not something to skip over; it is not a "terms and conditions" page. Read it completely before requesting an account.

What an account on the Test Scratch Wiki is

A portal to help internationalize the Scratch Wiki
A way of getting in touch with other interwiki editors
A way for other interwiki editors to get in touch with you

What an account on the Test Scratch Wiki is not

A status symbol or a bragging card
A place to learn a language - it's meant to help speakers of other languages, not for you to improve your grasp of a language.
A one-time thing - don't join and then go inactive in two days
A place to take out your anger for getting banned on Scratch - contact the Scratch appeals team instead

What a good account request must include

The language wiki(s) you want to contribute to
Your Babel language level in the languages you speak
A short explanation of why you want to contribute
The title of a page you would like to edit or create first

What a good account request must not be

Blank
Devoid of any useful explanation ("I want to join because I want to edit pages")
Abusive or inappropriate for Scratch in any way ("let me in or I'll stalk you")

With that in mind, go ahead and make your account request!