Nobody knows. There is a romantic story that he was wanted for poaching and had to leave town but that is unsubstantiated gossip.
As to how, I'm sure he walked.
William Shakespeare was born in Stratford on Avon.
Probably his decision to leave Stratford to look for work in London.
William Shakespeare was born and educated in Stratford-upon-Avon, a small market town in the county of Warwickshire in the English Midlands.
stratford
Stratford- England
stratford
William Shakespeare was born in Stratford-Upon-Avon, England.
The exact date when Shakespeare left Stratford for London is not known. It was betweem 1585 and 1592 - see the related question below.
William Shakespeare grew up in Stratford-upon-Avon in Warwickshire, England.A town in England called Stratford-on-Avon.
William Shakespeare's home was in Stratford, England.
William Shakespeare was born in the town of Stratford-upon-Avon in Warwickshire, England.April 1564, Stratford-upon-Avon, United Kingdom
He was baptised in the church in Stratford.