Check your TV
First you need to check your TV and figure out what type of mount is suitable for it. Many TVs work with VESA standard i.e. you can get a VESA compliant mount. In case your TV does not work with VESA standard, you can always buy the mount of the same manufacturer.
Fixed or movable
You need to make a decision whether you want your TV to be fixed or movable. Movable wall mounts are expensive but you can adjust the television screen according to your desired position. On the other, hand fixed mounts are cheaper but they are not consumer friendly. In case you are watching the TV from different angle, you might face problems.
Articulated wall arm
You need to determine whether you want an articulated wall arm with your movable mount. This arm is extended from the wall in order to attach an LCD or LED TV. It might be costly but you can easily move these arms or lock them in a place.
Check the screen size and weight of the TV
Before buying the wall mount, you need to know the weight and screen size of your TV. Then buy the wall mount which can hold more weight than the weight or size of your TV.
Check the wall mounts from your local stores or from internet
You need to check different wall mounts either from your local electronic store or from the internet. After you choose a wall mount, you need to examine it and check its condition. You need to watch out whether there are many anchor points in order to hang the TV. Also, watch out for the base and angle brackets in order to check they are well supported.