Note: Profile is called Shape now. Creating holes in flat surf | Blender Tricks

Note: Profile is called Shape now. Creating holes in flat surfaces is easy by beveling vertices with a specific Shape value, then extruding them as you like.

Here’s 5 minutes of topology tips about low poly triangle rotation, reducing the number of quads, adding loop cuts to cones / triangles, straightening out edge loops, flattening and smoothing out geometry.