"In the winter, whatever fears you have about being exposed and sleeping under the stars, completely intensify. There are less people on the street; you're more alone. The long, dark, cold, rainy nights leave you physically and emotionally insecure, because you have no protection whatsoever."
Erik is 46 years old and has two daughters. He slept rough for a year after falling into problems with alcohol and is currently waiting for a house while staying at a charity hostel.
Rough sleeping, as with homelessness in general, is a particular problem in London. According to the Combined Homelessness and Information Network (CHAIN) database 8,096 people slept rough at some point in London during 2015/16, an increase of 7% compared to 2014/15.
In 2008 the Mayor of London committed to end rough sleeping by 2012, but not only has the target has not been met, it's evidently getting worse.
Jim, 52, who used to sleep rough but is currently in temporary accommodation, says during the winter he never slept. "I found the most difficult thing was that the nights are so much longer - and you have to stay up all night and sleep in the day in order to stay safe.
"I used to cycle all night to keep warm and sleep in the day. So from 6pm to 8.30am I would be cycling all round London."
Stew, 48, is currently sleeping on the streets and agrees the long nights add to the danger.
"I always sleep in a place where it's very light and there are CCTV cameras. Other people I know have been set on fire, kicked and beaten up."
So how can we help? Desiree Shepherd is manager at The Vineyard Community Centre in Richmond, south west London. The centre offers refuge, showers, haircuts, cooked breakfasts and support for those in need.
"When people see homeless people begging, the easiest thing is to give cash. When in fact it's not helpful and even detrimental in many cases," says Desiree.
"We can't keep up with the demand for warm clothing during the winter here - we need gloves, socks and thermals. We did not have any to give last year, and it's imperative in the winter months."
From speaking to the men and women at the centre, good quality, warm and waterproof clothing came up every time when asked what they needed most.
"Other than warm clothes, a tent would be really good. It keeps the rain out and means you always have a sort of roof over your head," adds Erik.
An Oyster card is also more helpful to give than money, according to Stew. "I'll be totally honest with you, if people could give you a weekly or a monthly bus pass as a present, that would be really, really sound. Because when you've got a bus pass you can get to where the food is anyway and being on a bus - you're in a shelter."
For centres like The Vineyard, every little helps. "I think there is so much pleasure to be taken out of giving. The amazing thing is, each donation has the same value. It could be one can of beans, or a crate. It could be £1 or £1,000. With giving, the fulfilment is always the same; the amount you give makes no difference," says Desiree.
"But without the help from the community, we would not be able to run our service. Each bit of help - from volunteers, donations, skills, from the church - comes together to create impact and change for the better."
Warm clothing, long-life food, a tent and an Oyster card are all helpful donations to give to the homeless. There are also many centres, like the Vineyard Centre, and fundraising events you join in with in the run-up to the festive season. Here are just a few:
The Advent Sleep Out Challenge
The Church Urban Fund have launched the Advent Sleep Out Challenge as a way to raise money for the 4,000 beds they are providing for the homeless this winter. Hannah West attended a challenge on 11 November and this was her response when asked if she would do it again. "Absolutely we would! Simply because you can have so much fun raising money for a great cause!"
When: There are over 75 events across the country happening in the run-up to Christmas.
Where: There will be a Westminster Abbey Sleep Out on the 9 December, but head to CUF's website to find other London dates and locations.
Find out more: www.sleepoutchallenge.org.uk
The Street Bag Project
Mark Morrell started The Street Bag Project as a simple way of helping those in need. The idea is to fill a rucksack with items for the homeless this Christmas.
"It's so important to help those in need as we don't all realise what a fine line it is to become homeless and you could need that hand up one day. Besides it costs pretty much nothing to make a massive difference," says Mark.
When: On Saturday 17 December, he and many other volunteers will be handing out the bags in Kingston, south west London.
Where to donate: You can drop off bags at St Peter's Church, London Road, Kingston Upon Thames, Surrey, KT2 6QL before 17 Dec or on the day. Bag collections can also be arranged.
Find out more: www.facebook.com/StreetBagProject
Crisis at Christmas
Crisis at Christmas is Europe's largest volunteer-led event and this year they need over 10,000 people to help bring in over 5,000 homeless guests in from the cold. "Guests will be able to take advantage of life-changing services, as well enjoying food, warmth and companionship at what can be a terribly lonely time of year," says Simon Trevethick
Where: There are ten Crisis shelters across London where you can help.
Find out more: www.crisis.org.uk/pages/volunteer-christmas.html
HuffPost UK is running a fortnight-long focus around helping others this Christmas. Giving Back will shine a light on the organisations and individuals making a difference in their community, tackling issues such as loneliness, homelessness, food waste and financial struggle. We'd also love to hear your stories.
To blog for Giving Back, email email@example.com. To keep up to date with our features and find tips on how you can make a difference this Christmas, follow the hashtag #GivingBack.