Baby burrfish, pony pennings and pencillings,
and other weirdness from the sketchbook...
Practice practice practice; and eventually your audience will be able to tell your Olympic dressage rider from your working cowboy; your striped burrfish from your lizardfish, and your 1768 tops'l schooner from your 1812 tops'l schooner. Sketchbooks can go to the aquarium, the zoo, on a colonial era vessel balooshing across the Bay, to the beach, to the bottom of the sea (dive slates and crayons are waterproof). I make much use of my digital camera too, but a sketchbook (especially the hardbound ones that look like real books) helps you observe your subject closely, seeing many details you might have missed. And you can practice practice practice without committing to a fully finished opus of epic proportions.