Hi, you're welcome.

I'm not too concerned about the page number, I just pointed it out so you don't accidentally wind up doing more work than you need to in the future.

For making use of the space on the page, it is totally fine to just have one drawing per page so long as it takes up the majority of the page. So for example this lobster and this copepod make good use of the space available.

For making sure that your drawing will fit, if say you have half a page left and want to fit another drawing in without making it minuscule, you can make some observations from your reference to help you figure out how big to draw your first major forms, and where to put them. I've done a quick analysis of this lobster photo to describe some things I would look for.

I'd start by finding the parts that stick out furthest left, right, up and down, to help figure out the general proportion of the whole construction. Is it tall, wide, or squarish? This guy is a bit wider than he is tall, so I'll want a space on the page that is wider than it is tall, ideally.

Then I figure out how big the first forms I want to draw will be, compared to the overall size of the construction. This guy is almost 2 body lengths wide. The body is also near the top of the allocated page space, and over towards the right. That gives me a good guess where to put my first forms, and how big to make them.

Proportions are secondary to construction in these exercises, so it's more important that they feel solid than to have the proportions accurate. But I do find making careful observations from my reference and planning my constructions helps me stay in control of the scale of my drawing. I hope thinking about these things will help you too.

If you do end up running out of space on the page it is alright to just draw part of the creature. Just "cap off" the part you're not drawing, like we cap off the ends of our branches in the lesson3 branches exercise.

Hope that clears it up a bit for you.