Subdue...

Subdue has basically the same tasks as sweeping, except you never need another person to help.  They include:

Training with a skilled master
Cleaning the windows
Sweeping the floors
Watering the wildflowers
Practicing on critters
Practicing on the mannequins

So you probably want to know what all these involve...well read on.

Training with a skilled master

Like with every other skill in the guild, this simply involves visiting one of the Master Footpads and having them instruct you in the art of subdue.  

Cleaning the windows

Head to the storage area and get yourself a soft rag.  Find a window and RUB it with your rag.  Windows take about 10 minutes to get dirty, so if you have more repetitions than windows, you'll just have to wait.

Sweeping the floors

First, get yourself a broom and bag from the tool rack. Then find some scattered dirt, and make sure nobody else in the room is sweeping it. Then simply PUSH the broom and it'll make a pile. Once all the scattered dirt is in a pile, simply GET pile. Periodically you should LOOK in your bag to see if it is full.  Once its full, take it back to the rack where you got it from and PUT it in the bin. If you find there is no dirt around, go and PUT the bag in the bin, even if it's not full, it will generate more dirt.

Watering the flowers

Head down to the storage area and get yourself a watering can.  Then find yourself a bunch of wildflowers, kneel down and WATER the wildflowers with your watering can.

Practicing with critters

To practice with a critter, first you need to find one old enough for you.  See the section in the FAQ's on finding a critter to train with, then just go and subdue it a few times. 

Practicing on the mannequins

First, be sure to GO MANNEQUIN.  Then, make sure the mannequin head is CLEAN by CLEANing the MANNEQUIN.  Once it's clean PUT a MELON ON the MANNEQUIN.  Then you can SUBDUE the MANNEQUIN.  Make sure you're not hiding when you do this, because that won't work.

Other stuff

Now, a couple important notes about subdue.

First, and foremost it does NOT work against any undead.

Second, dagger based weapons work best, and provide a +10 to your MS.

Also, a good hit on a critter can cause it to fall to its knees. Basically the more ranks you have, the more likely this is to occur.