Because of problems with spam, contributors to a project's wiki need to be granted karma. Do NOT change permissions for Anonymous users without first consulting with Infra@

Space Admins (there is at least one space admin for each project) will see the 'Space Tools' link on the left navigation bar. Click the link to see a page like this: 

You'll now see the current permissions matrix. To add individual users, click on that section's Edit Permissions button

The system prompts you to enter your password again to gain access to administrative functionality; then you can add user accounts and click Add. By default they will only have the same permissions as anonymous users. 

Now you can choose the permissions you wish to add for each individual. 

If the user does not appear in the dropdown

There are circumstances that cause the user not to appear in the field shown above while you start to type. If you know the username, you can safely type it in. The permissions will be set.

Finally click Save all at the bottom of the page to commit the changes.