I have an apartment here, and one in town, where I stay a few nights a week; it has a terrace with a nice view of the sea. It's modern and private. At the palace it's great to know you have a lot of staff around. It's easy and practical. But sometimes it's too much: "Can I be alone for a minute!" Hence the other place. I can receive friends more easily there.

As kids we'd have family breakfasts, sometimes made by my mother [Princess Grace], although she tended to cook for us more up at our country place, Rocagel, above Monaco. Nowadays my father has his breakfast in his room and I do my own. There's a kitchenette and sometimes one of my sisters, Caroline or Stephanie, will be there. Or a friend may come and see me. I cook my own breakfast — scrambled eggs, whites only, with the uncooked yolk on top. What I don't make, but the chef does, is porridge — very good for your insides.

I drink fresh orange juice and Chinese, Japanese or earl grey tea, and I take these great effervescent multivitamins.

I try to reserve an hour a day to exercise. This morning I was in my gym at 8.30, but it depends on my schedule. In the days when I was much more active with bobsledding — I've been in five Olympics — I'd go to the gym at midnight if I was really pressed for time. Terrible!

At the palace there's an in-house tailor who makes the staff's uniforms, and sometimes I will have clothes made by him. But usually, as I am always in suits, I'll buy my stuff straight off the rack — like this one, by Hugo Boss.

Unlike the British royal family, the Prince of Monaco has executive power, and justice is done in the head of state's name — that being my father, Prince Rainier. Not to criticise your Queen, but it's much more hands-on here. The running of Monaco has many aspects and my responsibilities entail much more than people think — from foreign relations, which is why I travel so much, to social issues. Monaco is a village of one square mile that has the feel of an international city; you have to be a diplomat, spokesperson, and understand the businesses here, know the various charities. I'm sports administrator for Monaco; there's the grand prix, football. Then there are the construction projects that come to us for our consideration, like the little peninsula that will be the second stage of the addition we've already made to the harbour.

Unless there's a big committee meeting, people mostly come to me, although I enjoy meeting people in their workplace and seeing how they operate. My mother used to have this office. She used to say I could have it in a few years, and when she passed away I took it over. It has a desk side and a lounge side. I've tried to make it a little more masculine without changing much, but it's cluttered with family photos and trophies. It does have a great view of the port. I'm not a huge collector of art pieces. I did the whole stamp-collecting thing, and pens and keyrings, but nowadays I keep every accreditation — security tags — I have ever worn to events. Keep them under the mattress, in a box. No kidding!

I try and lunch with my father three times a week, sometimes dinner as well. In the summer, lunch is by the pool in the palace grounds — there's a new mist-making system that cools the area where we sit — and when it's hot you don't want to eat a lot, so it's usually a salad and fish. Or I might be at the beach club with my nephews, playing volleyball or tennis. If I could have chosen a profession I'd like to have worked with kids — a sports educator or a counsellor in a summer camp. Perhaps I'll have my own children one day. There are some girlfriends, but nobody in particular right now.

There are always paparazzi around. And it's not only the press that follow you — several years ago I was out on a friend's boat, and some people on a nearby boat took pictures of us and sold them to whatever magazine it was. But I don't let the gossip columns bother me.

I don't pay attention to it, unless they write something completely derogatory.

Once all my meetings are over and I'm not on call officially in the evenings, I have several buddies who I see. It's hard for me to relax in Monaco, especially at functions, as all eyes are on me, so to speak, but with friends it's possible to have a relaxing dinner. I like trying new places, like Pacific, which has Asian food. Normally I stick to a glass of wine with my meal and maybe once in a while a beer or a vodka. Occasionally I'll go to Jimmy'z, the nightclub — not as much as I used to when I was younger, though, unless it's for a special celebration.

I have a tendency not to be in bed before 1am. I always have to make calls or read up on things. I read in bed with the TV on in the background — usually sport, as I prefer to see movies in the cinema. And when I'm about to sleep, I think about what went wrong in my day and how I need best to improve for the coming one. But I try never to lose sleep over any issue. It's not worth it."