The workflow itself is quite simple just typ in the keyword "lay" (or chose another of your liking) followed by:

• full = Maximize
• left, right, top, bottom = Halves of screen
• topleft, topright, bottomleft, bottomright = Quaters of screen
• center = Center of screen (with 10% border)
• 11,12,13,21,22,23,31,32,33 = Thrids of screen
• 11-12,11-13,11-21,11-22 ... = Some other sizes based on thrids
• togglefullscreen = Toggle full screen mode of active window (if possible)
• movecenter = Move window to center of screen (no resize)
• movetopleft, movetopright, movebottomleft, movebottomright = Move window to edges of screen (no resize)
• grow, shrink = resize window by 1/6 of screen size with sticky screen edges
• 720p, 1080p = resize window to video resulution (e.g. screencasts)
• ... well the script is quite flexible, so I'm waiting for suggestions

It is multi-screen-able. Even though you cannot move windows from one screen to another (yet?) the scripts tries to figure out with screen you mean (depending on the size of the visible area).

Important

This workflow only works if Alfred is included in the list of Accessibility applications, which can be found under System Preferences > Security & Privacy > Privacy > Accessibility (in previous MacOS version this was done via Graphic User Interface (GUI) Scripting)