To answer your question, execute one mark per line throughout most of the process. Then closer to the end, you can go back to clarify specific overlaps by adding further line weight in certain areas. You'll notice that this is how I approach my demonstrations.

Moving onto your revisions, there are a number of issues that stand out to me. I've pointed them out directly on your work here, but here are the key points:

• In the first drawing, I noticed that you drew leaves that were structurally similar to those in this example, but instead of applying the approach shown there, you took a completely different route. This suggests that you may not have gone through the lesson as carefully as you could have, or more likely, you didn't review the material before starting your revisions, and forgot that it was there.

• In drawing those leaves, the flow lines of each section of leaf appear to be drawn without the kind of care and attention that they require. The flow lines, being that they establish how the leaf moves through space, are incredibly important. Make sure you're executing each individual mark to the best of your ability.

• For your cactus, instead of drawing one of its major forms as being a little more complex (making the form a little more tapered on one end, having it swell through the midsection, etc. all add little bits of complexity that may not be suitable for the first phase of construction), don't be afraid to let the forms inter-penetrate. Allowing them to intersect like this, then defining the intersection itself with a contour line is a great way to build up a structure with pieces that are as simple as possible.

• When it comes to building up complexity on top of a simpler structure, it's very easy to do with flat forms like leaves, because we can alter those silhouettes freely without worry that we're going to flatten them out (since they're already flat). Doing so with a form that is more three dimensional however is not as simple. This is something we tackle more in the next lesson, but as explained here, it is very important that we interact with these forms strictly in three dimensions - wrapping new forms around them, or cutting back into them along their surfaces, rather than just within the two dimensions of the page. That said, subtractive construction is better suited to geometric and hard-surface objects, rather than organics such as plants and animals.

Overall, I think that when you approached the core underlying constructions, you were somewhat distracted by the overall complexity of the whole image you were pursuing. This caused you to make a lot of sloppy marks, and to perhaps put less than your full capacity into executing each and every mark to the best of your current ability. I really cannot stress this enough - those early marks may seem less important than the details you add at the end, but it is the opposite.

As such, I'm going to assign the two pages of drawings again, with one additional caveat: I don't want you to add any texture. Just focus on the core construction. As a side note, you can - and frankly should - stick to simple subject matter. Don't worry about forcing yourself to draw a lot of different objects or forms all at once. Simple plants with few parts that allow you to focus more purposefully on each mark without getting distracted by the overall complexity are far more useful for this exercise than aiming for something more 'impressive'.