Sketchbooks are personal, so each artist will have a specific preference, but there are some qualities which every artist will look for.
Paper: The type of paper a sketchbook contains should be paired with the medium used and the artist’s sketching technique. Lightweight bond paper, a familiar smooth, crisp stock, is great for general sketching with pencil, pen, colored pencil and marker. Wet media like watercolor and heavier marker sketches will work better on heavier paper. Most sketch paper will accommodate light pastel and chalks, but textured paper is a better choice for more involved work in friable (crumbly, powdery) media. Some books contain toned (colored) paper, which is particularly nice for pastels.
Binding and Cover: The type of binding on a sketchbook can affect durability, portability and appearance. A sturdy perfect-bound sketchbook (traditional square binding like a standard hardbound book) is long lasting and looks great on a shelf, but this type can be bulky for transport. Perfect-bound books also restrict working into the spine, and can be a little clumsy to hold when opened.
Spiral-bound sketchbooks allow for working all the way to the spine. Pages can be turned completely around the back, making this type of book compact and easy to hold in one hand. A spiral binding adds bulk, however, and can snag when pulling out of a bag. The best spiral bound books are finished with the wire ends crimped inside the coil to avoid catching on other items.
Tape-bound sketchbooks have a nice, square spine, but this type of binding is not as durable as perfect-bound books. Pages can become loose, and the binding adhesive may split over time if the book is flexed heavily. Some books bound with thermal adhesive are more durable than others, however, and can withstand heavy use and transport.
Rigid board-type covers are nice for providing support when working, even serving as a makeshift drawing board. Larger hardback sketchbooks can be less portable, though, and can sustain corner damage in transport. Soft cover books are easy to pack or, in the case of small ones, slip into a pocket. Durable plastic covers resist wear and moisture. Leather-bound books can be embossed for personalization.
Size and Shape: Because portability is a factor with sketchbooks, it’s important to select the best size and proportion for the artist’s work and travel habits. Some artists prefer a larger sketchbook despite the added bulk and weight, while others insist on having a small book on their person at all times.
Standard proportions for sketchbooks may not work for every artist. Books with long, horizontal pages are great for landscapes, sequential illustration/comic strips and dividing pages into blocks.
Square corners may not be as good as rounded ones for pocket-size books, which need to slip in and out quickly.
Removable Pages (or not): Not everyone intends to take drawings out of a sketchbook for display, but for those who do, spiral bindings facilitate easy removal. Some have pages that are perforated to create a clean appearance instead of a ragged, torn edge that needs to be manually trimmed.
Notation: Artists who combine sketching with keeping a journal may like a sketchbook with half ruled pages. Usually these have ruled lines on the lower half of the page, and an open area at top for sketching. These are great for recording a trip, or for planning larger works of art based on sketches.
Materials Storage: Lots of artists tuck a pen or pencil into the spiral binding of a sketchbook, but some include a built-in slot for this purpose. Artists who make a habit of always carrying a sketchbook will appreciate this feature so they never have to scramble for a drawing instrument.
Availability of Replacements: Many artists try to stick with a favorite type of sketchbook as long as it’s still being manufactured. Some styles have been around for decades. There is always some version of a black faux leather, perfect-bound book, though the brands sometimes vary.