you don't - you need to change the number of cells on your spritesheet, because the size of the selection is relative to your spritesheet.
please take a look at the special signs of the filenames.
! means "this is an object sprite" instead of an NPC sprite. NPC sprites are shifted a few pixels up to make them look as if they are walking inside the grid, instead of the grids lines. This should not happen for object sprites like doors.
$ means "single sprite of 3x4 cells". Without $ the engine expects to get a spritesheet of 4x2 sprites or 12x8 cells. Your spritesheet is only six cells wide instead of 12, and it has probably too many cells above each other to fit.
additionally, you need to remove the title line above ("walking") because that will never fit, but be displayed on screen as part of your sprite - and the same goes for the divider lines.
I strongly suggest you go to the help file to learn how the sprites are formatted, then choose your image program and follow this tutorial to make a correct spritesheet:
Time and time again people who want to create their own sprites are asking for pre-made empty/framed templates because they can't work without them. And they don't even understand how limiting that is. Templates are crutches - bad crutches to be precise, because if you need a premade template...