There are two styles of divisions in this game. The
Old Style Division is what you may be used to in AGEod games. If you're not familiar with them they work like this:
Buttons you need:
1.

2.

3.

4.

5.

6.

7.
1. Organizational Special Orders Menu
2. Enable Divisional Command allowed
3. Enable Divisional Command not allowed
4. Combine Units allowed
5. Combine Units not allowed
6. Split Unit allowed
7. Split Unit not allowed
If your factions is allowed to form divisions and you have not reached the limit of the number of divisions your faction is allowed:
- Select the leader to whom you wish to give a command of a division and check if he's active this turn1).
- Click on the Organizational Special Orders Menu button to open its special orders buttons.
- Look for the Enable Divisional Command button on the far right. If you do not have this button displayed, your faction is not allowed to form divisions. If it is grayed out, you cannot form a division with this leader. The causes my be:
- Your factions has already reached the limit of the number of divisions your faction is allowed to form.
- Your selected leader is not active1).
- Your selected leader already has divisional command.
- Your faction lacks the assets to form a division (it costs a small amount of money to form a divisional command).
The tool-tip of the Enable Divisional Command button will give you information on this.
- Once you've pressed the Enable Divisional Command button and created a division with your leader, his name tag on his unit in the Stack Panel will become beige, and you are ready to start putting units into your newly created division. While the division commander is still selected, use <Ctrl><click> to select one or more units and then click on the Combine Units button; alternatively you may press <Ctrl><c>. You may continue to do this until your division has reached 18 elements.
You may add units to an
Old Style Division at any time it has not reached its limit by combining units into it as above. You many also reorganize it by splitting it up to take out units by selecting the Division and clicking the Split Unit SO button, or alternatively pressing <Ctrl><d>. It is advantageous to to Drag-n-Drop™ the Division into its own stack first to not get its constituent units mix up with others in the stack.
New Style Divisions are created with pre-built Divisional units. These may be combined with any leader at any time, even if the leader is not active, but the Division is then limited to consisting of only that divisional unit. You may however also create an
Old Style Division as I explained above and combine a Divisional unit into it, thus having the best of both worlds

.
If anything isn't clear, feel free to ask question.
1) You can see if a leader is active by checking one of these:
If he is the stack commander and the envelope on his stack on the map is light beige, he's active. If it is brown, he is inactive.
If he is the stack commander select his stack and click the his stack's Stack Tab to see the Stack Detail Panel in the lower-right corner. If the envelope is opened, the stack commander is active. If it is closed and brown, the stack commander is not active.
Hold the mouse pointer over his unit in the Stack Panel and read the tool-tip. If it says, "This leader can actively lead units this turn", he's active. If it says, "This leader cannot perform offensive actions this turn", he's inactive.
Hold the mouse pointer of his stack's Stack Tab and look at the Star(s) next to his name; Golden means active, gray means inactive. In this illustration, Johann von Reisch is active, but Franz von Werneck is inactive.
