Do those two things and see if you are able to connect from a remote box to the server as a user who has administrative privileges. That is just to make sure that you are ABLE to connect.
Recommended practice is that users have only limited privileges - enough to do what they need to do. So once you have established that you are able to connect from remote computers, create users and grant them privileges on the database that they need to access. There are step by step instructions here: http://msdn.microsoft.com/en-us/library/aa337562.aspx Also look at the links at the bottom of that page.