You will see that user’s screen. If he is a project worker his account will look something like this:

Hit the link “Tasks”, you will see all tasks assigned to this user:

Click on one of them:

Hit the button “new log”.
Now you will see the Task Log Form.
Let’s assume the user has completed 12 hrs. Enter some information in the “Description” field. Check the boxes for whoever you’d like to receive the email update:

Then click the button “update task”.
Now the task log will be added:

Check your email. You should have the update in your inbox.
This way, everyone who is involved will be in the loop at any time and from anywhere.
Finally, let’s create an invoice for work completed.