This article illustrates how to set list permissions in SharePoint.
1. On the left hand side of the page you want to change permissions for select Tasks.
2. Click Settings and select List Settings.
3. Under Permissions and Settings click on Permissions for this list.
4. Click Actions and select Edit User Permissions.
5. Select desired users to edit, click Actions and select Edit User Permissions.
6. Select permission level and click OK.