Make a small paint mixing station
Give mixing, testing and cleanup separate places so colours remain identifiable through a painting session.

A small mixing station can make a limited desk easier to use without turning it into a permanent paint bench. Start with the medium you actually use. Water-based model paint, solvent-based products and two-part coatings have different handling and cleanup requirements. Keep the setup specific to the product instructions rather than borrowing a cleanup method from another kind of paint.
Place a suitable palette on a stable protected surface with room for the model and a test piece. Arrange the containers so that reaching for one does not carry a loaded brush over an open bottle. Keep drinking cups and food away from the area. Use clearly identified water or cleaning containers and store them separately from household tableware.
Prepare a small test surface that resembles the model's primer and texture. A colour mixed on a white palette may look different over a dark base or across rough stone. Apply a little to the sample and let it reach the condition required for judgement. Wet appearance alone is not a reliable record of the final finish.
Label mixtures you intend to repeat. Note the product names and approximate proportions using a consistent method. A brush load is variable, so it is better suited to a one-session adjustment than a precise recipe for a large terrain set. If consistency matters, use an appropriate repeatable measuring method without contaminating the original containers.
Keep clean mixing tools apart from tools used to remove dried paint or apply texture. Return lids promptly and wipe container threads only by a method suitable for the product. If you use a wet palette, confirm that it suits the paint and follow its maintenance instructions; it is not a universal storage solution for every medium.
At the end of the session, photograph the labelled test samples and record which mixture was applied to which part. Dispose of residues and cleaning liquids according to the products and local arrangements. Pack the station only after containers are securely closed and the work surface is ready to handle. A compact setup succeeds when it can be restored without losing the identity of the colours you just used.

