Always aim for the head, bows have a special multiplier for a charged headshot.
Stay in cover to charge.
Bows are very weak at the start, and only useful if you can kill the target in one shot. Recommended to acquire only when you have Orokin Catalyst to super charge the bow right away.
Leading targets for horizontal and vertical headings is necessary at greater distances.
Charging can be cancelled without releasing the arrow using the reload R button (Press reload button while holding the left mouse).
All "charge weapons" (except Angstrum and Opticor) are now capable of holding their charge during a sprint, and as long as the user starts the charge, they are able to finish charging while they are still sprinting. This allows for more mobility to the user such as charging their weapon in cover, then run into the room and to unleash their first shot at first sight at the enemy immediately.
Using elevators and opening co-op doors also does not cancel the charge, however hacking consoles and opening lockers will.
Sliding when you are about to hit the ground (from any height) is very useful for keeping your charge instead of losing it by rolling.
As of Update/Patch 7.8.0, Headshots will not be counted at the end of missions, when using the Paris.
After charging an arrow and firing it while zooming, the next arrow you fire will not be drawn from the quiver, and instead the Paris and your hand will jerk very slightly. The next shot will show the reloading animation correctly.