TAKE ONE PART air-fare de-regulation, add fuel uncertainties and a steady stream of oil-price increses. Mix well with fallen dollars and rapidly rising hotel rates. Blend in a larger-than-ever portion of people on the move - and there you have it, the recipe for a summer travel stew.

It's quite a dish, but you may be able to season it to taste by knowing something of what's going on.

In the Air

Big demand, big changes. Fare and schedule alterations pop up every day and mean two things of special note.

One is the Importance of Reconfirming: This is especially necessary if you buy (or bought) tickets on a scheduled U.S. flight to a relatively small city, say, a month or more in advance. Reasons: U.S. airlines can now pull out of certain markets entirely and on relatively short notice; there have already been some canceled flights because of fuel shortages and more are not unlikely. When one route changes, timetables on another may be revised.

You needn't be overly alarmed by any of this, but since the airlines have something less than a perfect record of informing passengers of changes prior to check-in time, it's smart to stay tuned.

The Civil Aeronautics Board has strongly recommended that carriers give passengers advance notification of dropped flights and assist in rebooking them - at the same fare - but for the most part they are not required to do anything other than refund the buyer's money.

If you want to give yourself all the protection you can, ask what you're entitled to in the event of a delayed or canceled flight. Not all carriers assume the care and feeding of "stranded" low-fare passengers, and that may be a shopping point to consider. Besides everything else, there are still reports of labor unrest in Europe of the kind that in the past few years has severely affected some airports and air movements.

A side note on passengers' rights in the event of delays or cancellations: Scheduled U.S. carriers can no longer claim that the CAB prohibits them from changing rules or giving refunds to accommodate seriously inconvenienced passengers. For instance, they can, if they wish, let someone who's been hung up for several days change an "unchangeable" return date without a penalty.

In the event of a tighter gas crunch than predicted, airlines can generally be expected to cancel the flights with the fewest passengers and the fewest domino effects on equipment schedules. At present, though, there are no forecasts for any areas being harder hit than others.

The Second Thing to Note: The fast-changing air-fare scene needs continuing attention, too. Virtually all of the major U.S. scheduled airlines now guarantee their prices, meaning they won't nick you for more if increases come after you've paide but before you fly. This has not been the case with foreign airlines, which, according to their tariffs, could demand the price in force at the time of takeoff, but this position is subject to change. If pushed, though, all will refund money if their price on your type of ticket comes down before you fly.

That also means watch the ads. Unless you've bought a ticket that can't be changed without penalties, you can - if you find something better - turn in what you have and get your money back.

Charter Passengers: These travelers are in the process of acquiring some boons, too. Since May 1, anyone buying either a charter flight or a tour using a charter flight departing after July 1 cannot have the air fare raised any later than 10 days before departure. Moreover, the passenger has a right to drop out wih a full refund if even a timely increase is for more than 10 percent.

If You Buy, You Might as Well Fly: Scheduled airlines routinely overbook, so in heavy periods like the months coming up, you may find yourself with a ticket but no seat unless you learn the rest of the story. Ask for instructions, since there's usually a check-in desk deadline and a boarding, departure-gate deadline, and if you miss either you could be bumped without compensation.

Normally, on overbooked flights, carriers will ask if any passenger will give up his or her seat for a price. The amount offered is up to the airline, but if there are no takers at the first price, the ante is likely to be upped - since passengers bumped involuntarily must be paid the value of their tickets ($37.50 minimum, $200 maximum), twice the value if they can't be reaccommodated within two hours domestically, four hours internationally.

There's a king-sized exception to remember, though. Most foreign airlines offer less - or no - compensation to passengers bumped from return flights to the U.S. Again, this may be a shopping point worth consideration in view of predictions of jams today and jams tomorrow.

On Land and Sea

Quite a few tour operators are going after business by guaranteeing they won't add "surcharges." That's the good part. However, the bad part can be around in the fine print, since what's guaranteed may be only the "land" portion (hotels, meals and sight-seeing), not the transportation portion. What you need to know, of course, is whether any increase is allowed, how late it can come, and whether you can drop out and get all your money back if you don't like it.

The new CAB rules on charters allow charter tour buyers to drop out without penalty if major changes in cities, dates or hotels as well as prices are made prior to departure. Such changes after departure can, in many situations, entitle the buyer to at least a partial refund. Without a doubt, it's wise to check these protections with those offered on any other type of tour - but don't accept verbal assurances without understanding that they're not worth the paper they're not written on.

Hotels have rarely, if ever, had it so good, as rising prices quickly followed rising occupancy rates. But even when you've got the money they still may not have the room. By the same token, like the airlines, what they may not have today they could have tomorrow. Big hotels especially, are ripe for repeat tries. Note as well that cancellations of lower-priced rooms can occur after you've agreed to take a higher-priced room, so you could profit by rechecking this, too.

Also, since they've few in number, many large hotels keep their rock-bottom-rate rooms to sell by themselves rather than through booking agents.

If at first you don't succeed in making a reservation, remember, too, that a hotel may be "sold out" because a tour operator signed up for a big block of rooms - and the tour operator may still have a "package" that meets your needs.

Sold-out cruise ships occasionally may be available, too, as "tours." Again, it's something to bear in mind along with the fact that extra fuel charges already have been announced by quite a few. If you find one that doesn't have a surcharge, ask, of course, if they'll guarantee none will be added.

Train and bus bookings are reportedly hitting all-time highs for this summer. It's nonetheless problematical how many people are "stayers" and how many will opt out when and if the gas-pump panic eases. For the moment, though, the difficulty in getting through on the phone to company reservations offices rivals getting through to the airlines. Best advice is to try in the early pre-breakfast hours or late at night.

Nothing's perfect, but attention to such details is at least one way to stay cool through what looks like a hot and heavy summer travel season.