https://www.skillshare.com/en/classes/improve-your-drawing-today-12-simple-warm-up-exercises/1161419873

In this class I’ll show you how and why I warm up in 12 different exercises, giving you all the tools you need to start each sketching session with confidence. All whilst improving your art!  My name is Toby, known as 'Toby Sketch Loose', and I know that warming up before sketching is something I really should do more of. When I don’t warm up, too often my first sketch goes awry, wonky or just lacks clarity and confidence.  Because of these mistakes and learning through experience I developed a series of warm up exercises that I can use to fit my mood and the scenes I’m planning to tackle. These exercises suit all abilities, ranging from simple marks through to characterful thumbnails like the ones below.