Mangle! One of the most dreaded topics in Mikrotik. People get chills at the mention of this topic. But frankly speaking, I see no reason for that. I can however understand the fear because I was once like them.
Today I am going to show you how easy it is to configure a mangle rule. These mangle rules are powerful tools in the hands of network engineers because they go on to use them( mangle rules) to enforce several policies on the router. You can control user traffics and downloads as well as prioritize traffics, using mangle rules.

Here, I will show you how to mark packets using mangle rules. These marked packets are used when setting up queues for bandwidth managements or when prioritizing packets.
Just look at the images below and follow the steps.
Source: http://www.timigate.com/2016/10/how-to-create-mangle-rules-on-mikrotik.html#more