There are a number of options to create a rig in order to animate your character, from manually building one to using various 'automated' addons.
One of the most used addons is Rigify, which is installed with Blender by default. While it does make rigging much easier, there is still a fairly set workflow to follow.
From the Blenderartists forum, I see a number of beginner mistakes often repeated. So in this short video I show a few of the most common ones and how to avoid them.

CHAPTERS
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00:00 Opening
00:27 Intro
00:38 Don't Parent the Metarig
01:32 Never Delete the Metarig
02:26 Always Apply Scale
03:09 Moving Disconnected Bones
03:49 Outro


Mesh from Blender Human Base Meshes: https://www.blender.org/download/demo...