Tips for facing a stronger player?

I'm playing a much higher rated opponent than me (he's 1800 and I'm 1200) on Friday.

Any tips on how to last long?

How to last long ... ? Take your time between moves?

Possibly a more helpful answer from me would be to advise you to look at some of the established openings and defences out there so your first few moves set you up in a good position - of course problem with this is there are too many variables and things that could change

Normally if i am against a player i think is much better than me i concentrate on making sure all my pieces are covering each other and try to make sensible trade offs without allowing him/her to get me into forks

Of course the problem i have is i am not that bright or that fast at spotting things, and often i end up running out of time

Having said that i am fairly new to the game myself so probably not the best person to help you

Analyze and pick three candidate moves and analyze all of them and make whichever you think is best

Hide behind a potted plant and then when he thinks the coast is clear jump out and kick him in the family jewels. Just make sure to withdraw from the tournament before the next round starts or the police will get you.

Just kidding of course but this really happened I hear in Canada in the 70s.

Play your regular game.  Maybe it's just my particular problem but when I face much higher rated players I tend to play openings that I don't usually play.  Maybe it's because I get intimidated and feel like my regular openings aren't good enough somehow.  This usually ends very badly for me so whatever you do, stick to the openings you know and play your regular game.     

At some point early in the game he is going to get tempted and want to attack earlier than usual. He has to be thinking he wants to take you out early. I say in about move 20 - 30 he will want to end the game.

If you have Black play defensively solid. If you have to exchange pawns make sure your ahead or it is an even exchange. Castle in first 10 moves. Get your Knights to Nc6 and Nf6 early. Watch out for him 0-0-0 to have a pawn attack on your king side castle(if you do play 0-0). Play the KID if he plays d5, at best he has to work to win the game with some simple trick. It he plays and e4 opening I would say play the Sicilian but that might be to his favor as he should understand it better than you in chess.

Chances are you might not win but you want him to work for it. Best chance if by the Middle Game and he/she has no advantage they are going to start to get a little frustrated during the game. That is good. He will then take time between moves and you get to scan the board for targets to attack also.

Spill water on his racket

Put a scorpion in his golf buggy

Put itching powder in his ice hockey socks.

Oh. Wrong sport.

in another words: play the board not the player.

Do NOT play to last long. Instead play the very best moves you can find as Estragon, kco, melvernboy are suggesting.

1. As mentioned keep to your normal style.

2. Since (s)he is 1800 there may be some games of him/her stored online. Google it, find out what openings (s)he plays. Have a look at those (you can also ask for help on a specific opening here)

3. Be sure to ask for a post mortem why you lost afterwards, it helps you improve 

Have fun!

Keeping your mind focused on the position rather than wandering off into other things, whether it is your opponent's rating, what you fancy for dinner or the pretty girl you met the night before last is one of the truly hard things to do. Looking at the top GMs when they play I suspect they can do this without effort but most of my otb opponents seem just like me - very easily distracted.

Anyway my tip is to enjoy your game. It is quite a nice position to be in - that of the underdog. Losing is no disgrace while winning, or even drawing, gets you bragging rights. So play your natural game, don't try too hard and have fun. :)

You know how I can easily beat a 1200 player?

I don't have to do anything. I can just wait around and they'll mess up their position by themselves.

Play solid, don't create weaknesses in your own camp, don't commit to silly attacks, and let him do the work to come and get you.

And remember this: if you don't know what to do, don't move a pawn.

Let us not beat around the bush, you're likely to be horribly murdered.

However, the following quote has some resonance: "Death smiles at us all. All a man can do is smile back." (Proximo)

Go in there, take your medicine and revel in your defeat.

For added theatre, sweep the pieces from the board by way of resignation and then, make a striding exit, audibly humming Darth Vader's Theme.

Make a name for yourself.

Exactly. Your only chance is if he falls for a cheap trap.

I say, don't play like you normally play. DO play the man, not the board.

Complicate the position as much as you can, and hope he makes a mistake before you do.

There is a one in 1000 chance for you to win or draw this way.

There is a 0 in 1000 chance if you play 'properly'

On what do you base this opinion?

-edit-

If you enjoy playing this way you should do it though...

During the game focus on what you are going to play and play your best chess.

Another tip is this. If youn play your natural game and soon enough find that good moves are really hard to find with your position deteriorating and then a position is reached where there is just no way to hold and you lose quickly from there - do play the game over afterwards. Your opponent has made good positional moves in the early middle game and that is what restricted your options. Look for those moves and see why they were good and why they tied you up. My own (rather slow) progress has come from very gradually understanding about open files, outpost squares, how a bishop can dominate a knight, how to deny my opponent space and so on. It is easy enough to get practice at tactics but a game against a markedly stronger opponent strikes me as one of the best ways to get insight into some of the positional aspects of the game. You have already invested time into examining the position as it evolves and playing the game over so that you see how your stronger opponent's evaluation differed from your own will get a return on that investment.

Do not play a gambit

What do you mean with "high ranked"?

I'm not 1800 yet but I'm preparing a line against ANYTHING that my opponent can play. The less good an opening is, the easier it is to prepare against it. I'm not saying the Bird is a bad choice, but anybody 1800+ should have something prepared for it.

If you play bad lines your opponent will be out of his preparation...but he won't need it. Against a stronger opponent you should play as solid as you can imo.

defense  , a la Petrosian's "safety first".

I played someone 500 points higher by setting up a defensive position. After an hour he launched an attack and blundered. Of course a blunder may never come, but is more likely with an impatient opponent.

Complacency by the opponent also helps. I've beaten or drawn several players 400 points up who didn't play at their level, probably thinking I was an easy win,  ...often I am  : (  .