Ed Sheeran, 26, regularly sells out stadiums and is one of the best-earning, most renowned pop stars worldwide. But there were times when the young musician led a less glamorous life.

In his early career, after playing a gig for a handful of people, there were times when he would sleep on the London Underground or even spend nights on heating vent outside Buckingham Palace.

His is the classic "rags to riches" story. At age 16, Sheeran dropped out of school and left his home in the quiet town of Framlingham in Suffolk for London, where he signed up for classes at a music school and toured the city's pubs.

Couch surfer

For two-and-a-half years, he slept on a succession of sofas, played up to 300 gigs every year and took writing classes during the day. He was never really homeless, he says in his 2014 book "A Visual Journey." He was having a good time, but didn't live in the cold streets, he says, arguing that he spent most nights playing in pubs.

The few nights he really did spend on the streets of London inspired Sheeran to write the song "Homeless" on his self-published 2010 extended play record (EP), "Loose Change." Back then, Sheeran sold his CDs online and in person, carrying a stack around in his backpack.

Once, at a gig in a homeless shelter, he met drug-addicted prostitute Angel. Touched by her story, he dedicated the song "The A Team" to Angel

It was first released on "Loose Change" and later as the hit single of his first album + ("Plus").

At home with Jamie Foxx

Seeking gigs and contacts, the British singer headed to Los Angeles in 2010. He performed at a club owned by US actor Jamie Foxx, and the actor's manager invited Sheeran to play on Foxx's radio show. Foxx was so taken by Sheeran's music that he invited him into his home, offering the singer the use of his private recording studio at no charge.

A highly motivated Sheeran returned to London. He describes his feelings in "A Visual Journey," remembering how he felt at the time: if he was able to record music with a rich film star in LA in just a month, who knows what he would be able to do when back in the UK. But the breakthrough was a long time coming, and not much changed back home - at least at first.

A call from Elton John

Sheeran began to attract larger audiences, but that didn't net him a better income. Record companies still weren't interested in signing him. There came a day when he had no money for the trip home after a sold-out gig, and he actually felt like giving up.

Doggedly, he continued on his own, however, and next offered his new EP "No. 5 Collaborations Project" on iTunes in January 2011. Within 24 hours his recording had jumped to second place on the iTunes charts - and Elton John called to congratulate him.

The phone kept on ringing after that call, with record companies suddenly vying to sign the new shooting star.

New album, world tour

In the six years since, Sheeran has released two albums and additional EPs. His latest album ÷ ("Divide") hits stores on March 3. Two singles - "Shape of You" and "Castle on the Hill" - shot to the top of the charts when they were released simultaneously in early January.

Next stop: selling out stadiums around the globe. Sheeran's world tour kicks off in Turin, Italy on March 16, and includes five concerts in Germany (March 20 in Munich, March 22 in Mannheim, March 23 in Cologne, March 26 in Hamburg and March 27 in Berlin).