Everyday I turn trash into cash! In return for my box tops, labels and other proofs of purchase, the big food manufacturers fill my mailbox with a steady stream of cash refunds and free products.

You can do it too.

The secret is in a large, well-organized collection of proofs of purchase. We call them POPs for short.

Don't worry about your family calling you the "garbage king" or "garbage queen." The insults quickly stop as the refunds start to arrive. Especially if they include sporting goods for Junior and similarly prized gifts for other members of the family.

Here are my tips for saving and organizing your POPs to really cash in on refunds:

Save every POP you can find. Start with the national brands. Save box tops and bottoms, netweight statements, ingredient panels and, of course, universal-product-code symbols and proof-of-purchase seals.

Save space by peeling the label from its cardboard backing.

When you're saving everything, it's often easier to fold the whole package flat instead of cutting out all the POPs.

Save cash-register tapes since many refund offers require sending the tapes along with your other POPs.

Keep your growing collection of POPs out of the way of the rest of the family. Store them in envelopes, shoe boxes or cartons.

File your POPs alphabetically by name of manufacturer or product, whichever is more common.

Keep a carton in your kitchen to receive the packages, cans and bottles from which you will later remove the POPs. (Be sure they are clean or you're inviting ants to a picnic.)

Why save everything? Bcause the manufacturer of a product such as cereal may make a refund offer this month that requires a box top, then weeks or months later may make another offer asking for a UPC symbol that you can get from the same box.

The POP you save today may bring you a $2 refund next month -- or next year.

One parting tip: When you cut out a POP such as a weight statement, be sure to write the product's name on back. POPs are worthless if you don't know where they came from. If you have any questions or suggestions, please write to me in care of United Features Syndicate, 200 Park Ave., New York, N.Y. 10017. Occasionally we publish them. CLIP 'N FILE REFUNDS File No. 5: Sauces, Sugar, Syrup and Salad Dressings NFN -- no form necessary; REQ -- refund form required. (all listings are subject to manufacturer's geographical limitations and local laws.)

Buitoni Foods Corp., P.O. Box NB-204, El Paso, Texas 79977. REQ. Free jar of spaghetti sauce. Send labels from three 15-ounce jars or two 29-ounce jars of Buitoni's Spaghetti Sauce. Expires Dec. 31, 1980. o

R.T. French Company, P.O. box 2269, Rochester, N.Y. 14609. NFN. Receive $1 refund plus 33 main-dish recipes. Send top thirds of 5 packages of French's sauces and gravy mixes. Expires Dec. 31, 1979.

Hunt's Ketchup Free Offer, 1300 Highway 8, box 9895, St. Paul, Minn. 55198. REQ. Free bottle of ketchup. Send neckbands from 2 bottles of Hunt's Ketchup. Look for hang-tag offer. Expires Dec. 31, 1979.

Kraft Squeeze Mustard & Hot Dog Refund, P.O. box 443, Chicago, ill.

60677. REQ. Receive $1 refund. Send 1 universal product code cut from Kraft Squeeze Mustard, 1 front label from any brand of hot dogs and 1 front label from any brand of hot-dog buns. Expires Dec. 31, 1979.

Ragu Italian Restaurant Offer, P.O. Box NB-444, El Paso, Texas 79977. REQ. Receive free jar of sauce. Send 1 label from any size and flavor of Ragu Italian Cooking Sauce. Expires Dec. 31, 1979.

Wishbone 8-ounce Offer, P.O. Box 8580. Clinton, Iowa 52732. NFN. Free 8-ounce bottle of salad dressing. Send neckbands from two 8-ounce bottles of any variety of Wish-Bone Salad Dressing. Expires Nov. 30, 1979. File No. 6: Meat, Poultry, Seafood And Other Main Dishes

Bumble Bee Free Offer, P.O. Box 713, Young America, Minn. 55339. REQ. Free can of tuna. Send 2 labels from 13-ounce Bumble Bee Solid White Tuna. Expires Dec. 31, 1979.

Gwaltney, P.o. Box Nb-421, El Paso, Texas 79977. NFN. Receive $1 coupon. Send 1 label from Gwaltney Boned 'n Tender Ham. Expires April 30, 1980.

Free Morton House Stew. P.O. box 8525, Clinton, Iowa 52736. REQ. Free can of stew. Send entire labels from 4 cans of Morton House Stew. Expires March 31, 1980.

The Rath Packing Company, P.O. Box 682, Waterloo, Iowa 50704. NFN. Receive 50-cent, $1 or $2 refund. Send proof-of-purchase logos cut from package fronts of Rath meat products. Ham has proof inside. Two proofs get you 50 cents, 3 get you $1, 5 get you $2. Expires Dec. 31, 1979.

Rupert's Certi-Fresh, P.O. Box 1080, West Covina, Calif. 91763. REQ. Free package of fish. Send 1 ingredient flap from Rupert's Certi-Fresh Sole in Butter Sauce or Sea Bass in Lemon Butter. Expires June 1, 1980.

Wilson Foods Corporation, P.O. Box 823, El Paso, Texas 79977. REQ. Receive $2 to $5 refund. Send guarantee slips from inside any variety of Thomas E. Wilson Canned Hams. Two slips get you $2; you get $1 more for each additional slip up to 3. Expires March 31, 1980.