If you did not get this achievement from your first playthrough then don't worry, you can access the missions (along with your current score for each mission) from the missions tab in your phone.
Each mission will have secondary objectives that contribute to the 100%. These will vary from times, accuracy, damage taken, headshots, items destroyed or incidentals. Some will be difficult to obtain on the same attempt but they do not need to be achieved on the same try, they are applied to future efforts also.
For accuracy and headshots, use the pistol as it is very powerful and accurate. Damage taken should not be a problem as you are given full health and armour (i think) at the start of each attempt.
To preview the objectives for each mission, go to the pause menu, go to the stats tab and view player.
If you have to restart from a checkpoint you automatically score 0% on the mission even if you complete it (i think).
To get this achievement you will need to score 100% (achieve all secondary objectives) on all missions.
Edit: Using taxis will void your score for that particular attempt, sorry