Here is a great process breakdown from SANG JUN LEE for Creature and Character designing, going from Thumbnails to the Final Design.
Read it and apply his process to the character work you are doing for Projects 1 & 2.
Gnomon Workshop - access through Library portal
Here is really comprehensive video on how professional Concept Artist will use Thumbnailing to start their character concept work.
Check out the other videos in the series and search for how other artists do it in similar or different ways.
The video on the left gives some fascinating insights into how a professional character designer approaches a new design.
Sergio Pablos' career in animation spans over three decades. His work is well known as a Supervising Animator on Disney films such as "Tarzan" and "Treasure Planet". At the helm of his company The SPA Studios, he's also known for having developed the original story upon which films like "Despicable Me" and "Smallfoot" are based on.
In addition to this, he has worked as a character designer, story-board artist, and most recently as writer and Director of the first original animated Netflix film, "Klaus", all of which have garnered him several nominations including Best Animated Feature at Academy Awards, the Annie Awards and BAFTA.