Dear Damian (half my age),

You say “sure, what’s the worst that could happen?” too often for someone who has witnessed the worst that could happen.

On a related note, you have never had a good idea at 5am.

No. Never.

But don’t worry, mistakes are good. Mistakes are where you learn. You will learn a lot in the next two decades. Just remember, there’s no need to turn embracing failure into an art form.

You are going to write a book soon. The first newspaper review will proudly display the headline: “Avoid this book.”

Get over it (quicker).

But first, you need to take college more seriously. For example, try getting out of bed before the crack of noon. The quilt cover is not the periphery of your whole world. Come to think of it, neither is college. A few weeks after you graduate, no one will ever ask you again what grade you got.

It is, though, probably time you stopped bringing your washing home to mum (even if you could get away with this for another while).

Being a parent is hard work. You don’t know that yet, but you will (oh boy, you will).

And it is a thankless one. But it shouldn’t be, so ring mum and dad and thank them: not for all they did for you, but just for not murdering you at any stage. Because they often had just cause, and surely thought about it.

And ask them for advice, even when you think you don’t need it. You do.

Stop taking advice from random people.

Learn to cook.

Cook.

You’re good at focusing and concentrating on something. You are really bad at picking the right thing to focus and concentrate on.

If you don’t go out this weekend, don’t worry. You didn’t miss anything.

If you do, stop singing – everyone’s watching (on a side note, so to speak, all the best music has already been written.)

And I’m not sure why you don’t already know this, but you simply cannot combine sports and alcohol. It just doesn’t work. You might as well hold a hurley in one hand and a pint in the other. You are doing justice to neither.

Pick one and concentrate on it.

No, the other one.

And when you only have money for either alcohol or food, choose food more often.

On a specific note, cancel all plans for your 21st birthday party. You are not invincible, and neither are your friends. On the night, five people will end up in hospital, in three separate incidents. It’ll even be brought up by a senator a few days later.

Trust me. Cancel. It. Now.

You need to stop planning to travel to exotic places, and actually get going. Faurther than Co Cork. Just remember to be back in three years’ time on a certain night in a certain pub when a certain girl makes the mistake of sitting beside you. Among many, many other things, she’ll organise your surprise 40th birthday party. And everyone agrees, you could never do better than her (there was a poll, it was unanimous).

Write more cards. Send more flowers. Listen more. Talk less, but speak up. Don’t upload that photograph. Don’t get blonde highlights. Mind your back – in every way.

And stop being so hard on yourself. Sometimes, no one is to blame. Shit happens.

There’s good news and bad news about your career dreams.

Playing in Croke Park, Wembley or Lansdowne Road won’t quite work out, but then you never really thought it would.

But hard work beats talent every day of the week, so stop moaning about being as useful as the “b” in “dumb”.

Friends will help. You have many friends. In 20 years, you’ll have a few. You won’t lose any along the way, you’ll just learn who the real ones are.

There is no cure for life, but it can be managed efficiently. For example, you don’t have to spend every penny (it’ll be cents soon enough) every week. It’s not a law.

At some stage in the next 20 years, at least learn the basics of how to manage your finances. And buy shares in any company that comes under a heading of “social media”.

You will spend the next 10 years renting, before a financial adviser convinces you to “stop flushing money down the drain” and to take out a mortgage.

Punch him in the face.

Then run, because your body is far from indestructible, no matter what a certain Skoda wielding taxi driver thinks in a few years’ time. So stop filling it with pizza and chips. Eat the odd apple, you’ll be thankful in 20 years’ time.

Also, watch out for Skoda-wielding taxi drivers.

Speaking of cars, you may love that old Ford Escort XR3i, but the most valuable thing you own is your word.

It’s not even close, and it’s not because the car has a large hole in the floor. Just make sure your word never does.

And remember, whatever you decide to do, do it now. What you think is a very long time from now is really soon.