Jeez, some of this thread? WTF? ....Nothing special needs to be done here.

You stabilise the battlefield. Artillary pins enemy troops. Artillary, Long range rockets and SF degrade enemy supply lines and Command Structure. SF and the Air-Force then destroy enemy air defence systems and airfields. Keep going until you establish a battlefield where you can gain air superiority.

You've achieved that? .....Congratulations, you're now ready to attack. Armour and troops move forward with close air support over-running any enemy defensive networks (trenches, command posts) Artillary/SF both soften up attack points and cut supply lines to halt any chance for reinforcements.

Should the attack run out of steam then its time to stabilise the battlefield again. ...Rinse and repeat until a rout occurs (rather than a retreat)

The metaphor of war being a 'meat-grinder' came about for a reason. It can be slow and relentless.