add an exception to the server's Windows Firewall for TCP 1433 (or whatever port you use)
enable TCP as a client connection protocol for the SQL Server instance by opening up "SQL server configuration manager"
open management studio, right click on the instance, click properties, then click connections along the left side, check allow remote connections)
Change Server Authentication to SQL Server and Windows Authentication. By default, SQL Server 2008 Express allows only Windows Authentication mode so you can connect to the SQL Server with current user log-on credential. If you want to specify user for connect to the SQL Server, you have to change Server Authentication to SQL Server and Windows Authentication.
My issue was something was already running on port 1433, so I changed to port 1435 in "SQL server configuration manager" under "SQL server network configuration", then protocols for my instance, right click on TCP/IP, then go all the way to the bottom on under allIP change the bottom value, leave dynamic blank.
How you connect to SQL on a different port from with-in management studio:
ip,port (127.0.0.1,6283 -add a comma between the ip and port, no spaces)
How I discovered what was using which port
netstat - na for list of all open ports
netstat -ano for a list of all open ports with their process ID, then open task manager to see what process is on that port