In terms of first-hand eyewitness accounts, there are none that describe what Jesus looks like due to the relative obscurity of Christianity and a disdain towards religious art due to it being associated with paganism.

One of the earliest depictions of Jesus came from a fresco in a church in Dura Europus, where Jesus is depicted performing one of his miracles where he healed a paralyzed man. Here, Jesus is displayed with short hair and a clean-shaven face, although this was fresco was painted around 200 years after Jesus had died.

Son with no eyewitness accounts of his appearance, scholars have relied on identifying what the average Middle-Eastern man looked like. This was undertaken in Professor Joan Taylor's book 'What Did Jesus Look Like, where she concluded that the average Middle-Eastern man at the time stood 1.70m (5'5") tall, possessing olive-brown skin, brown eyes and black hair - with this judgement coming from archaeological remains and physical and textual descriptions. She further states that lice was an issue with Israeli and Egyptian people, so to mitigate this they had their hair and beards relatively short, not the long flowing locks that Jesus is so often depicted with.

This corresponds with a rather famous depiction by Richard Neave of what the average Middle-Eastern man looked like. With their research stating similar that Jesus had dark features, although their estimate for his height had him at 5 feet.

So essentially, we do not have first-hand evidence of what Jesus looked like. It's well-known of course that he is not the long haired, blue-eyed person as shown so often in Western civilization, so to base it off the typical appearance of a Middle-Eastern man at the time Jesus was short (in comparison to his modern portrayal), black-haired, brown eyes with olive to brown skin.