This achievement is actually very simple, but some may find it confusing to begin with.
The first prerequisite to this achievement is completing the Thieves Guild main story line and obtaining the Darkness Returns achievement.
After doing this, you are tasked with the following.
Speak to Delvin and Vex in the guild to receive small tasks relating to certain holds in Skyrim. You need to complete a total 5 missions in each of the following places:
Whiterun
Markath
Windhelm
Solitude
- These jobs are very simple and usually consist of burglary, pickpocketing and lockpicking.
- I'd advise you to have two tasks at once to minimize the time you'll spend doing this.
- You can choose any of the jobs.
- If you have already completed 5 tasks in a hold and you receive another task for that particular hold, you can quit the task and obtain a new one by talking to the person who gave it to you.
After you've completed 5 missions in a hold, you'll be given a special task. Once again these are very simple.
After completing all the special jobs, you'll immediately start the final mission "Under New Management".
You will receive the achievement after completing this mission and obtaining your guild armour from Tonila.