To Create a new Window or Tab with a Specific Profile
You can assign keyboard shortcuts to the items in the Shell > New Window and New Tab submenus using System Preferences > Keyboard > Shortcuts > App Shortcuts to add shortcuts to Terminal.
For example, if you add
Homebrew ⌥⌘9
to the preferences, typing ⌥-⌘-9 will open a new terminal window with the Homebrew profile.
If you want to assign keys for creating tabs, you'll need to explicitly refer to the New Tab submenu using “->”. For example, I have this in my preferences:
Shell->New Tab->Homebrew ⌥⇧⌘9
Typing ⌥-⇧-⌘-9 will open a new tab with the Homebrew profile.
To Apply a Profile to the Current Terminal
You can change the profile of the current terminal using the Inspector window. You can use Shell > Show/Hide Inspector ⌘I to show or hide the Inspector. In the Inspector’s Settings tab you can use the keyboard to select a new profile—you can use the up/down arrow keys or type the name of a profile.