I`m also having trouble on military, how to organize them?
What's troubling you about it?
First, you've got to assemble a squad. Unless you want to be tacticool, I wouldn't recommend making your first squad led by the Militia commander, it is preferable to keep the commander at home if you want to be less fiddly when it comes to replacing lost recruits and you find you have to make a new commander before doing so.
From the military [p]ositions page, select as many migrants as you want for your first squad. To create a new squad, appoint a militia captain from the [n]obles screen once you have appointed the militia commander.
There are two optimal squad sizes, one has 3 Dwarves per squad yet requires more micromanaging for no real benefit, and is really only used if you want to have lots of squads. The other optimal size is multiples of 2 above 3.
From the schedules screen, give your first [o
]rder. When in the orders screen, cycle between what [o
]rder you want to give, at this stage you can ignore all of the orders apart from train. Give an order to train for 2 Dwarves [control the number of Dwarves you want the orders to affect with [-+ | */]] for every two Dwarves in that squad [minus one or two Dwarves to let them be off duty and drink/eat].
In the [e]quipment [U
]niforms page, highlight one of the uniforms you want to assign to your Dwarves. Don't worry if you do not currently have the equipment available, the Dwarves will automatically do so once better/available equipment arises. With the uniform selected, [shift] + [enter] assigns it to the entire squad.
Then go to anywhere you want your soldiers to be training, build a container or a cabinet, armour or weapons rack and designate that area as a barracks/armoury. Once that is done, enable your squads to [t]rain there. Again, don't worry about the other settings until you have grasped the basics.
Then go the military [a]lerts screen and under Active/training, highlight the squads you want to be on duty and hit enter. This will put them in that alert - it essentially means they will begin following whatever orders you assign.
Anything you want covered in detail like creating uniforms, effective weapons, barracks setups e.t.c.?