Argh! It's absolutely chucking it down and I've got to be at college Wednesday morning, not looking forward to it as I've never ridden in heavy rain before!
Well it might not still be raining on Wednesday...
But it will be good experience if it is. You need to learn where the water gets in and how quickly (it will get in, it's just a matter of time). I find that the worst place is the water running down my sleeves and into my gloves. It helps a lot to wear a cheap oversuit even over good waterproofs, you can tuck your gloves and boots inside the suit to make the entry route more convoluted. They also give a surprising amount of extra draught proofing and insulation. Then it just depends on how waterproof the gloves and boots are. No matter what it says on the package they have to be very good indeed to be really waterproof. I sometimes use waterproof overmittens but you need to be really familiar with the bike to be able to drive it while wearing them as they make it very difficult to feel what's going on. For that reason I use them only rarely for very long wet cold journeys. Handlebar covers are good as long as they don't interfere with your control, you need to check them very carefully. I had a pair on my 1200 Bandit and I only noticed that they gave problems when I got to over ninety, when they started applying the clutch and brake for me at the same time.
The cold hits you harder when you're wet, make sure you're prepared for it if it's a long journey. When you get there it might be nice to have at least a change of socks, and for a very long or very wet journey maybe a complete change of clothing in a waterproof bag. You might want to consider some means of hanging things up to dry. On the bright side, you'll soon make a name for yourself. Tough guy, or nut case.
Make sure the bike's in top condition and made ready. Lights and tyres are even more important in the wet and you'll have enough to worry about without wondering if you're going to run out of fuel. If you have a bike with an open chain final drive, oil it now. The chain will probably need oiling a
lot more often in wet weather, say every 100 miles at most. On a bike with an exposed final drive chain I take a little contact lens bottle full of 20/50 oil with me everywhere. Label it clearly so nobody puts it in their eyes.
Easy on the brakes, use the gears, keep it smooth, go slower into corners and
gently accelerate throughout. Braking while cornering is generally considered bad idea and in the wet it's very much easier to lose your grip that way. Watch out for slippery surfaces if the rain has followed a dry spell, wet tyre rubber dust makes a good lubricant. Give yourself a lot more room, nobody else will. Make sure the anti-mist on your visor works. Furniture polish (on the outside
only) might help. Try to stay away from vehicles which lift a lot of spray. Try not to scratch your visor wiping it with a gritty glove. Sometimes you may need to lift it just to see what you need to see, so don't be going so fast that the rain will blind you when it hits you in the eyes. It might sting your face but you can deal with that by gritting your teeth.
Be extra vigilant. Eye contact with other drivers becomes even more important, especially in mirrors (at this stage mostly your mirrors, unfortunately, but theirs too). Try to show people that you're battling with the conditions even if you aren't, they might even begin to understand. If you're leaving a lot of room in front of you then jerks on four wheels who have no idea about grip in the wet and make no allowances for it will hassle you or try to carve you up. So take command of your part of the road but try not to give too much offence. People will take offence anyway, practically the only thing you can do about that is watch out for your own safety in developing situations.
Start earlier than you need to. You can spend half an hour making new friends, drying your socks is a great ice-breaker.
If it gets bad, find a safe place to stop. Don't press on into danger because you've got to get there, you might end up at A&E instead.
I probably missed loads of things, think of this as just a few pointers. How far is the journey?