'At Christmas time, we usually do a lot of eating and shopping,' says Edwin Lau Che-feng, director of environmental group Friends of the Earth (Hong Kong). 'That's two of the main activities of Hong Kong people. But we also need to think about it in terms of environmental conservation. Many department stores will be trying to attract us with special promotions, but if we don't need those items, we shouldn't buy them as we are using up valuable resources from the planet.'

When preparing the Christmas meal, Mr Lau says, use organic produce wherever you can. 'Be a responsible consumer. There are several choices in Central, SoHo, Lan Kwai Fong and Mong Kok, if people want to eat at an organic restaurant,' Mr Lau says. He goes on to say that details of restaurants selling organic food are easily available on the internet.

Buy goods from local areas, so that the transport mileage from where the fruit and vegetables are grown is as short as possible. Check the labels on the products in the supermarket to see where they come from. Alternatively, buy from local wet markets, where the produce is fresh and not wrapped in plastic or polystyrene.

'People should try to eat less meat. Livestock bred for human consumption contributes 18 per cent of the greenhouse gas emissions that cause global warming,' he says.

Be creative when purchasing your Christmas gifts. Buy organic spaghetti and rice, you can even find organic wine. Friends of the Earth also suggests buying tickets to the theatre or the cinema, or charity vouchers for your friends and relations.

And be sure to take a look at the packaging. Metal is very wasteful, so whenever you can, try not to buy tins, (as in the case of mooncakes) unless you intend to keep them and reuse them. Ensure there is not too much plastic, cardboard and polystyrene in the packaging. If there is, choose another present that is less environmentally harmful.

Think carefully about the presents themselves. Try to avoid presents with batteries that continuously need replacing. It's better to buy toys that use recyclable rechargeable batteries.

There are many firms now that carry an environmental message - some perhaps a little more genuinely than others. Aveda cosmetics brand has made a point of being green ever since it was set up in 1999. It sources ingredients for its products in a responsible fair trade manner. The Body Shop, one of the earliest environmentally aware companies, is another responsible trader.

In Britain, environmentalists estimate that 1billion cards will have been thrown into the rubbish by the end of the Christmas season. Yes, those cards can be recycled, but why not send your Christmas greetings by e-mail this year, there are many fun cards to be found on the web and no trees will be wasted.

For Christmas decorations, Mr Lau recommends using a foldable-plastic tree that can be reused again and again, rather than a tree that has to be chopped down, then gets thrown into the landfill two weeks later. Hong Kong companies are big producers of LED and solar lights these days, so check to see what's available on the market in terms of fairy lights for the tree and general home decoration.

Otherwise, you can use normal electric decorations frugally. It's fine to have them on when everyone's at home to enjoy them, but make sure that you switch them off overnight. 'The same applies to the commercial sector,' Mr Lau says. 'Turn on the decorations and lights when the shops are full of people, but choose a more energy-efficient lighting system that can be switched off after hours when everyone's at home asleep.'

Try to recycle your shopping bags, and use recycled paper when wrapping the presents. When you unwrap your Christmas gifts, try to save the paper so it can be used next year. Friends of the Earth also suggests buying second-hand antique jewellery and other vintage goods.

When hosting a party, avoid using disposable plates and cups and don't throw away the aluminium foil when you've finished roasting that big bird.

'None of these things are particularly difficult to do,' says Gloria Chang, campaigner for Greenpeace China, 'but they all make a difference to the environment.' Ms Chang advises Hongkongers, many of whom are already in the habit of recycling, to try to maintain their eco-friendly habits during the festive season. 'It's important that people remember the spirit of Christmas,' she says. 'It's not always about spending as much as you can and giving the most extravagant presents. It's about enjoying quality time with your family and friends.'

With the above tips you can have a merry Christmas with a clear conscience. So, all together, 'I'm dreaming, of a green Christmas...'