Heraldry is a fascinating subject but can be difficult to get started, especially in the understanding and using of the language of Blazon.
DrawShield offers several ways to get started, and you can follow whichever most suits you, or combine more than one of these approaches.
Firstly, we have a Tube channel which includes an introductory video. It says many of the same things as this page but in spoken words!
We do have a Manual:User Guide, which is intended to work both as a tutorial and a reference. It begins with some basic topics and works towards more complex features. Each page includes a "Usage" section giving examples of use, and there are also sections from the "Herald's Notebook" providing interesting observations and snippets of the herald's knowledge.
If you are impatient to simply start creating some simple shields then use the Build From Parts page. This allows you to create a blazon and the corresponding shield image just be clicking on options. Although it is tempting just to "click and create" you will gain much more if you carefully study how each part is represented in the blazon text and you will be able to transfer this knowledge to the from a blazon page where the full power of DrawShield becomes available.
And don't forget the Gallery - all the blazons are available for every gallery entry so if you find a coat of arms that you like you can look at the blazon to see how it has been created.