Sometimes as an account owner you want to delegate the project creation to another user. Here is how you can do it. 

1. Go to Manage tab and select Manage Users ( Figure 1 ).

 Figure 1 

2. Click Edit button to edit the user ( Figure 2 ). You will find an option for allow this user to create project on behalf of you. The default value is No. 

 Figure 2 

3. Switch the option Allow this user to create project on behalf of myself from No to Yes. You will see a notification about the option being turned on ( Figure 3 ).

 Figure 3 

4. Now if you go back to the user list page, you will notice an "Delegated" label marking that you have delegated the user to create project on your behalf ( Figure 4 ). 

Now the user can create project, as well as edit/delete/archive, the project(s) that he created on your behalf. However, he cannot edit/delete/archive the projects you have created yourself. 

The users that will be put into the projects that the delegated user creates on your behalf will be counted against your user quota. 

 Figure 4 

Here is an article on how the delegated user can create project on your behalf.