In case your Steam profile suffered some changes and you would need to apply these changes to your Dota Trade profile, use Update button.
Personal note is used to provide some detailed info for other users. It's displayed on your profile page.
You can paste links to items/sets/heroes into your note. Read more here.
Maximize your chances of finding a nice offer! Share your profile with your friends.
Tradeshot is a nice picture that displays your wishes and offerings. Read more about tradeshots here.