If you are serious about sketching with confidence, all you need is a few hours and this:
https://simplydesignsketching.teachable.com/
Sketching with construction lines helps us to build our design ideas quickly and clearly. This video explains what construction lines are, how to use them in our sketching, and how they improve communication between the designer and the person reading the sketches. This method will help you to become an accomplished designer.
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