Think of your warmup page as just that, a warmup page, meant not to show anyone. It’s just a place to get the hand warm, to get the feel of the pencil pressure, and have all of those wonky lines go first before moving on to drawing something you actually want. If you are practicing basic drawing, then line art can be quite helpful for that. You might just want to start drawing some object, like a chair or a car, because every curve looks stiff for some reason.
On a warmup page, you only need one piece of paper or one page in a notebook. Use one corner for the left-to-right slow strokes (leave a small gap between each). Use another area for the left to right row of left arches, like so. Another corner could be circles, or ovals, and just keep the lines very light. It should not look “finished” if a circle is off shape or an oval is very wobbly. A page like that can look pretty active.
Straight strokes teach you to make directional marks. Curves teach you to make smooth marks. Circles and ovals teach you to make control marks as they go a full round. It gives you a different look. When you draw, a straight line might bend, or maybe bend down. That’s because your wrist is stiff. The curve might look too flat if you’re moving too fast, and the oval may not close if it slows down at the meeting point. Once you notice the pattern, you can see what you want to draw later, you can make a more accurate mark.
You can do the same strokes on a warmup page, but at a different pace. You can do several straight lines at a slower rate and then at a normal one. Do a couple of curves at a lighter rate and then a couple at a medium speed. To do an oval, make the oval go around the shape a couple of times instead of going from start to end and lifting the pencil. This can help the arm move more freely to avoid overworking lines with many scratchy ones.
The main thing that beginners struggle with is impatience. Your warmup might feel like you’re not actually drawing, and it’s tempting to move on quickly. If you just start drawing something, then all of your stiff lines will be on the first few lines when drawing your cup, plant, hand, or reference image. A warmup page gives you somewhere to go for those early strokes. This will also help you see if your pressure is too heavy when drawing construction and contour lines later on.
A quick warmup page will keep you fresh. If you spend too long, then you probably shouldn’t be on the page at all. A few minutes drawing is better than doing the whole page without noticing. Once your warmup is done, pick one thing from the warmup you want to carry into the next sketch. It can be drawing with lighter pressure, or a smoother curve, or a slower contour line, or a more direct straight stroke in drawing something box-like. Whatever it is, the point is that after the warmup you pick one thing that it can remind you of on the next draw.