Last winter, cockpits became miniature skating rinks and boats tilted at crazy angles as pilings and docks to which they are fastened were inexorably elevated by ice rising with the tide. But despite the forlorn look of many boats left in the water last year, most weathered the rough weather. It was the owners who suffered most, anguished that their summer pals might not survive the season of the mighty freeze.

Yet peace of mind for the upcoming winter can be attained with comparatively little effort and expense. Here are a few tips:

The great blocks of ice that filled many cockpits last year can be avoided by putting a cover over the area or, in the case of sailboats, by draping canvas over the boom to form a tent.

In a mild winter such protection may not be necessary. Snow that falls into the cockpit will soon melt and be dissipated through the cockpit drains. In a severe winter, however, the cockpit drains freeze so solidly that rain or snow can't pass through. Then the snow melts in a warm spell, only to turn to ice when the temperature dips again. If a lot of snow or rain falls, the cockpit eventually fills with so much ice that the stern is weighed down and substantial pressure is put on the cockpit sole.

Don't count too much on a cover, however. It can tear, or be dislodged by wind, and unless steeply angled, collect - and then pass - a certain amount of water. It's a good idea to visit the boat as soon as possible after every snowfall to shovel snow off before it has a chance to melt and freeze.

Deicers should be especially considered for woden boats, which were last winter's principal casualties. They can't stand up to ice like fiberglass hulls and damage to their caulking is common.But the best use of deicers may be to place them close to pilings; last year, damage to pilings and docks far outweighed damage to the boats themselves.

Provided sufficient deicers are used, leaving the boat in the water should be safe and even advantageous. Haulage fees are saved and the craft is perfectly supported and in most favorable storage environment. And if the boat is floating, the engine can get the therapy that goes with it being occasionally run.

On the other hand, the owner of a hauled boat knows that about all he has to fear from water is a tidal wave. If the boat is hauled, the slime and barnacles should come off at once. Otherwise, the bottom dries out and the cleaning becomes more difficult later on.

If the boat is stored on a trailer, jack up the trailer and place blocks under the axle so that the trailer rests on them rather than on the tires. Elevate the trailer tongue somewhat and remove plugs from the bilge and transom so water can drain. Trailer wheel bearings should be repacked with grease and the winch and rollers lubricated.

A cover that exceeds the boat length by several feet should be draped over a sturdy A-frame. The frame should be steep enough to keep water from collecting on the cover. The cover should be dense enough to keep out rain and snow but porous enough to permit air to circulate into the boat's interior.

Whether on land or water, boat interiors should be kept dry, airy and empty. Drain and clean the bilge and the head.Drain and flush all freshwater systems. Put nontoxic antifreeze in the water tank and work the pump until antifreeze flows through the spigots. Blow out the drain lines, if possible, and close the seacocks.

Raise the floorboards to ventilate the lower part of the boat. Turn up the bunk cushions and open refrigerators, lockers, drawers and doors. Open hatches, windows and lazarettes enough to permit air into the boat's interior.

Engines should be winterized in strict accordance with the manufacturer's instructions. Beyond the basic requirement to get antifreeze in the cooling system, it's a good idea to put some stabilizing fuel conditioner into the gas tank. The conditioner preserves the fuel through the winter and keeps the fuel system from clogging. Run the engine long enough to work the conditioner through the carburetor.

Fogging oil (rusting-inhibiting oil) should be fed into the carburetor with the engine running to coat the valve stems, valve guides and rocker arms.

The boat battery may be left on shore or on board, but in either case it should be attached to a trickle charger, a device that charges a battery only when needed. Check the degree of charge monthly with a hydrometer and add water if necessary.

Use dacron or nylon thread to repair small tears or frayed or broken stitching in sails. Even if they look clean, give them a fresh-water rinse. If they're dirty and there' space at home, lay out flat and scrub with a brush and mild detergent. If space is a problem try the bathtub or shower. Home laundries are not recommended.

Finally, visit the boat as often as possible and particularly after a heavy rain or snow. If it's in the water, check the mooring or dock lines. If it is listing or seems low in the water, investigate immediately. Every winter, a few boats sink because their owners turn their backs on their summer buddies a little too long.