I just recently joined the forums, but I've looked through a number of tutorials which have been no end of help. But, I'm curious as to how you map out a continent so it looks like it would be the size of a continent. (Strange wording, I know.) I'm also curious as to climates in fantasy cartography.

Here's two landmass I generated in Fractal Terrains:

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I'm not sure which one I'm going to use yet, but both are supposed to--at least, in my mind--be the size of North America. Length-wise, from the middle of Manitoba to at least south Texas; width, from California to North Carolina. I'm planning on moving these landmasses over to GIMP, tracing over them, and going from there. How does someone best communicate the intended size of a landmass? (The inland bodies of water will be filled in in the final drawing.)

As for climate, I'm aiming for something that follows the same logic as real world climates. For example, I'm planning on the northern quarters of both landmasses having a subarctic climate.
I guess what I'm asking is what are limitations and what liberties can I take? Am I constrained to mirroring real-world climates, or am I being thinking too much into it lol?

Any tips and criticisms are welcome.