As most of Granny speedrunners struggle with replicating some of the glitches used in Any% speedruns, I've made a few videos on how to exactly do them, its very simple, it depends on your skill level with controlling the character, if you're good with using Granny movement, these glitches should be easy.

Clipping from the Sewer to the Basement using the lift:

Clipping from the Basement Tunnel to the Sewer:

Clipping from the Backyard Workshop Tunnel to the Sewer:

Clipping from the 2nd Bedroom (where the book shelf is) to the attic using the chair:

Hope this helped :)