In order to change your preferences for how much you're expecting to be paid per hour or how many hours you would prefer to work each week, you need to go to your Profile page via your User Menu.
Once in your Profile page, click on the edit button next to your profile picture on the left side of your page.
A dialogue box should open on the right-hand-side of your Profile page.
Scroll down the dialogue box to the 'What is your expected hourly rate?' section and use the box underneath that to provide an answer.
If you prefer not to set a specific hourly rate for your work, you can click on the 'Negotiable' button instead.
If you would like to change your preferred hours of work, you can use the weekly-hour horizontal scroll bar.
Once you have completed editing your preferences, click on Save Changes.