Banner days can become a family tradition, right up there with Christmas stockings and Easter baskets. Party Color will make you a birthday banner to celebrate your special day in multicolor style. Made of felt, the banners have your name, your birth date, your greeting and gift pockets for filling with little gifts. Party Color will aim the pockets for skiers, for sailors, for any assortment of categories you suggest. And they will do all that for $15 to $20.

The proprietors get involved in other kinds of parties, too, by way of handmade centerpieces and favors. They cover mushroom baskets with fabrics, ribbons and ruffles. And stuff them with leaves and favors - small stuffed animals, gingham fruits, felt ice cream cones - on velvet ribbons which turn them into necklaces for the guests. Pick your party theme, and they will stuff a basket appropriately for $15 to $25. On a smaller scale, Party Color has devised perky felt animals backed with snap clothespines so they can be used as miniature puppets or to hold greetings or money. The polka-dot frogs, heart-bedecked pigs and such cost $1 each or seventy-five cents each for orders of ten or more. Think what they could do for the image of clotheslines.

Party Color . 8952 or 434-6333.