Coaches can be invaluable resources for athletes making their way through their recruiting mission, they can provide insight on how you're doing and what you should do next. For that reason it's a great idea to grant your coach access to your account which let's them see what you're up to in your recruiting process and advise you on what your next steps should be!
It's important to note that granting access only gives the coach viewable permissions, and they are not authorized to make any changes to your account on your behalf. They can however, see how your profile looks, review your college list, and take a closer look at conversations you've been having, which helps them stay up to date!
Be sure to check your "My Coach" mail inbox as well - it's an area where the coach can write you a short message about how your process is going.
If you want to grant access for a coach, navigate to the "Settings>Manage Access" section of the account!