The basic cycle
Cold or warm water, gentle cycle, mild detergent, no bleach and no fabric softener. Softener coats the yarn and dulls both the crispness of percale and the lustre of sateen. Tumble dry low and pull the sheets while they still hold a trace of moisture; hems settle flat and wrinkles mostly hang out on the bed.
Percale, specifically
Percale is the one fabric in the range that genuinely improves with laundering. The matte crispness you buy it for deepens over the first dozen washes. Iron it if you love the hotel finish; skip it and the finish is simply softer.
Sateen, specifically
Sateen keeps its sheen longest when it dries gently: low tumble or a line. High heat is the only real enemy, because it stresses the long floats that give the weave its lustre.
Blankets and protectors
The cotton blankets take the dryer without complaint. Waterproof protectors wash warm and dry low; high heat ages the membrane, and the membrane is the point.
Storage
Store sets inside one of their own pillowcases, in the tote they shipped in. Cotton likes to breathe; plastic bins hold moisture and give linen a shelf smell that takes two washes to undo.