1. Step The most obvious thing to is to press F11 while you are in-game (in GW2) and enable Vsync
2. Step Go to the graphic options and at the bottom check the box Vsync – this could already fix your screen tearing issue
3. Step If that doesn’t help and you use a NVIDIA graphic card, disable double/triple frame buffering
4. Step Still no dice? Then go on and try playing around with the Hz of your monitor
5. Step Right-click on desktop, click Screen Resolution
6. Step Click the blue Advanced Settings link on the bottom right
7. Step Go to the tab monitor and select a different refresh rate from the dropdown:
8. Step Still no luck? Read this related tutorial