Image source, Sauber

The only way is up for Sauber after a miserable 2014 season which saw the team fail to score a single point. It was their worst effort since joining the grid in 1993.

This year, the Swiss team have gone for an all-new blue and yellow livery and an all-new line-up in Felipe Nasr and Marcus Ericsson.

"We have learned our lessons and are confident for the new season," says team boss Monisha Kalternborn. "We have to improve and be able to fight for championship points."

Marsh-wiggle:, external Love waking up to a feed full of #F1 testing tweets and photos! Very clever camouflage on the Red Bull.

So which 2015 F1 machine is the best looking? Which livery tickles your fancy? And crucially what looks the quickest? Answers on a tweet, using the #bbcf1 hashtag, or a text 81111 (UK only). If you use the latter, don't forget to put your name on the message. I thank you.

We have a few more times on the board, with Nico Rosberg going quickest with a 1:23.653 in the Mercedes, 2.1 seconds ahead of Sebastian Vettel's Ferrari. Sauber's Marcus Ericsson is 1.1 seconds further back with Daniel Ricciardo two seconds adrift in the Red Bull.

Image source, Lewis Hamilton on Twitter

Lewis Hamilton has yet to sign a new deal with Mercedes, but when the time comes, the world champion says he'll be doing it on his own for the first time after severing ties with his management company last year.

Hamilton, whose current deal runs out at the end of 2015, says he is a "rookie" in this area: "I am 30 now. I am my own man. I know my worth.

The Briton, who hung out with, external Aloe Blacc during the season, adds: "I have read every one of my contracts in the past so I know what is and what can't go and what I can try to get."

F1 journalist Dan Knutson in Jerez: "Mercedes team boss Toto Wolff is on crutches after injuring his left knee in a gym accident during the off-season. He discarded them for the official team photo in the pit lane this morning. Wolff was also injured last July in a cycling accident with other team members, although that time it was an arm."

Red Bull have already had a more successful day than they managed this time last year. In 2014, Sebastian Vettel managed just two laps. After less than an hour of this year's first day, Daniel Ricciardo has clocked up four, including the first timed lap of the day - one minute 29.141 seconds.

Andrew Benson
Chief F1 writer

Image source, Getty Images

"Red Bull have thrown out the F1 rule book with a camouflage testing livery. They like to do things a bit differently - their pre-season media day was at an indoor snow slope in Milton Keynes - but this is clearly to make it harder for rivals to get a good look at their car.

"What they could not hide, though, was that the car bears a strong resemblance to last year's from the cockpit back, and that the nose combines much of last year's Ferrari, with the 'bump' on the end featured on this year's Williams. How teams have addressed the new regulations aimed at increasing front-end safety is one of the key talking points so far this season."

Image source, Getty Images

Ferrari had a shocker of a season in 2014, their worst for more than 20 years. There have been a series of major senior management changes with new team principal Maurizio Arrivabene setting the target of winning "at least two races" in 2015 after launching their new car.

As mentioned, four-time world champion Sebastian Vettel has joined the team, hopeful of turning the Scuderia's fortunes around much like his compatriot Michael Schumacher managed to do more than a decade ago.

"There is a lot of change going on, a lot of new people in new positions," says Vettel. "It takes time to settle in, but I am confident we are going in the right direction. But it would be wrong to expect a lot of us."

Image source, Getty Images

Here's the new Ferrari, in all it's glory, with Sebastian Vettel at the wheel. The German, sporting a white helmet with a German flag running along the top, is starting a new chapter in his career after leaving Red Bull, the team with which he won all four of his world titles.

Image source, Toro Rosso

After a slight delay, the new Toro Rosso leaves the garage with Carlos Sainz Jr at the wheel.

Sainz Jr, son of two-time world rally champion Carlos Sainz Sr, is making his Formula 1 debut this year.

The 20-year-old clinched the seat after winning last year's Formula Renault 3.5 series, the feeder championship won by Dane Kevin Magnussen in 2013 before he was signed by McLaren for 2014.

Andrew Benson
Chief F1 writer

Image source, Getty Images

"Mercedes start the season as favourites and the car breaks cover to the world's media for the first time on Sunday morning. The car ran briefly on a snow-hit Thursday afternoon at Silverstone last week, when both drivers took to the wheel, but Nico Rosberg is the man who gets the first full day's testing in the W06 Hybrid at Jerez.

'It's a great feeling,' the German said. 'I know how much work has gone into it. The factories are buzzing, the energy, the amount of work they put it into it, it's really intense. To finally see it doing what it's meant to do is a great feeling for everybody.'"

Image source, Red Bull

Red Bull are running a camouflage testing livery in Jerez. Very cool.

McLaren's Jenson Button:, external Morning from rather chilly but sunny Jerez. First day of winter testing today, don't expect too much from us [at] this test as it'll be mostly system checks. She's a beauty the MP4-30! #rememberlastwinter #Longroad #massivepotential

The action is already under way in Jerez, with Nico Rosberg (Mercedes), Sebastian Vettel (Ferrari) and Marcus Ericsson (Sauber) straight out of the blocks. McLaren aren't so sprightly.

Teams are only permitted to run one car, which means half the grid will have to wait until tomorrow to get their first taste of their 2015 car.

Nico Rosberg is in action for Mercedes today, with Daniel Ricciardo driving the Red Bull. Valtteri Bottas (Williams), Sebastian Vettel (Ferrari), Fernando Alonso (McLaren), Carlos Sainz Jr (Toro Rosso), Pastor Maldonado (Lotus), Marcus Ericsson (Sauber) complete the field.

Image source, McLaren

McLaren:, external Applying the finishing touches #FA14.

Image source, Getty Images

Just eight teams are in action in Jerez, with Force India deciding to pull out on "efficiency grounds" because of "limited learning opportunities".

The team, who launched their livery in a presentation in Mexico City earlier this month, had planned to run 2015 parts on their 2014 car, while development continued on this year's race machine.

A team spokesman denied financial issues prompted the move and refused to comment on reports that the team are allegedly late paying suppliers.

With Marussia and Caterham unlikely to make the grid, we'll have just nine teams and 18 drivers in action this season.

Mercedes will retain their driver line-up of world champion Lewis Hamilton and Nico Rosberg, with Red Bull fielding Daniel Ricciardo alongside the in-coming Daniil Kvyat.

Williams stick with Felipe Massa and Valtteri Bottas while Ferrari bring in four-time world champion Sebastian Vettel to race alongside Kimi Raikkonen.

McLaren stick with Jenson Button while Fernando Alonso makes his return to the team. Force India retain Nico Hulkenberg and Sergio Perez.

Toro Rosso field an all-new line-up of rookies Max Verstappen and Carlos Sainz Jr while Lotus retain Pastor Maldonado and Romain Grosjean.

Sauber complete the grid with a new line-up of Marcus Ericsson and rookie Felipe Nasr.

This year, the season will visit 20 different countries, across five continents. It'll start in Melbourne, Australia on 15 March and end in Abu Dhabi on 29 November.

In between, the teams will visit Malaysia, China and Bahrain before heading to Europe for Spain and Monaco.

Next they head across the pond for Canada before returning for Austria, Britain, Germany, Hungary, Belgium and Italy.

Then it's time to really clock up the air miles as F1 heads for Singapore, Japan, Russia, United States, Mexico and Brazil before ending in Abu Dhabi.

It's exhausting just thinking about it.