Go to menu Friends by clicking on the button located in the top right corner, then the menu will appear Friend Request from other people towards us, Find Friends, and Invite Friends.

Next, scroll the screen to the bottom to find the name of the owner of the account who has sent a friend request. Remember right, who's the guy?

People who have not received a friend request is easily detected because it says "Awaiting Reply", and there is no menu "Visit" on his profile.

Do a long tap on the profile photo or name of the person, so that it will automatically appear the dialog box "Unshare". If this dialog box does not automatically appear, tap the round icon in red with a white line horizontal in the middle to bring up the dialog box Unshare. Then, click "Yes". Ta da! You've finished cancel the friend request.