Crew XP GuideAs of Aug. 22, 2017, load up any story in Warstories and you receive a tank with a 100% trained perk and this achievement pops automatically.
Crew Skill/Perks are found in the "Crew" section in the "Upgrade" (push
in menu) sub-menu in the garage. Crew SKill/Perks are extra abilities you can add to your tank after you have achieved 100% mastery with a selected tanks crew.
In the "Crew" menu will be a listing of all the tank crew you currently have for every tank. Select the tank crew you want the Skill/Perk for and it will take you to another sub-menu with "Skills and Perks" in it. Selecting this takes you to a list of all the available Skills/Perks.
In this list are a variety of extra abilities you can train your tanks crew in. They each have an icon to the left of their name indicating whether it is a "Perk" (Lightening Bolt) or a "Skill" (Compass). Perks do not apply til they are 100% unlocked, Skills apply immediately and improve with each percentage point til you hit 100%.
If your tanks crew is not 100% trained yet the grey boxes under your crew commanders name for your tank will say so. You CAN NOT train a Skill/Perk til the crew is fully trained and a "Plus" icon appears. You can then pick a Skill/Perk of your choosing to train your crew on.
How much experience you get for your crew depends on how well you perform in matches. Most players will typically only see their crew XP go up 1% to 3% at a time. Keep in mind you only get 1/2 xp for your crew on matches you loose. This means you probably won't see it go up at all after a loss.
The achievement will pop in the after-action report immediately after getting 100% training.
A great Perk to go after first is "Sixth Sense." This Perk lets you know when you are in an enemies line-of-sight prior to you actually being spotted. I DO NOT recommend you go after this achievement til after you have unlocked "Mentor" for your "Skilled Commander" achievement. Mentor increases the amount of crew xp you get after a battle.