There are many hadiths which tell us what the Prophet looked liked.
Rabee'ah ibn Abi 'Abd al-Rahmaan said:
"I heard Anas ibn Maalik (may Allaah be pleased with him) describing the Prophet (peace and blessings of Allaah be upon him). He said:
'He was of average height, not too tall and not too short, with a pinkish colour, not very white and not dark, and his hair was neither very curly nor very straight. The Revelation came to him when he was forty years old, and he stayed in Makkah for ten years after the Revelation came, then in Madeenah for ten years. When he died, there were no more than twenty white hairs on his head and in his beard."
Al-Baraa' ibn 'Aazib said:
"The Messenger of Allaah (peace and blessings of Allaah be upon him) was broad shouldered and had thick hair coming down to his shoulders and earlobes. He was wearing red garments. I have never seen anything more beautiful than him."
(Reported by Muslim, Kitaab al-Fadaa'il, Baab Sifat Sha'r al-Nabi (peace and blessings of Allaah be upon him), no. 2338).
"He was neither tall nor short, and had large hands and feet. He had a large head and was big-boned, and the thin line of hair (starting from his chest and extending to the navel) was long. When he walked, he would lean forward, as if he was walking downhill. I have never seen anyone like him, before or since."
(Reported by al-Tirmidhi, 3570, who said this is a saheeh hasan hadeeth).
Jaabir ibn Samurah said:
"The Messenger of Allaah (peace and blessings of Allaah be upon him) was dalee' al-fam, ashkal al-'ayn and manhoos al-'aqib." Shu'bah said: "I asked Maalik, 'What is dalee' al-fam?' He said: 'Wide-mouthed.' I asked, 'What is ashkal al-'ayn?' He said, 'Big-eyed.' I asked, 'What is manhoos al-'aqib?' He said, 'His heels were not fleshy.'"
(Saheeh Muslim, Kitaab al-Fadaa'il, 2339).
Ali ibn Talib (R), a close family member and cousin of the Prophet , says –
The Prophet did not have a very fleshy face, nor was it completely round, it was slightly ovalish. He had a whitish skin with a reddish tinge (this means lighter brown), his eyes were large with jet-black pupils and his lashes were long. his joints were large as was his upper back. He did not have hair all over his body, he had a fine line of hair extending from chest to the naval. When he would walk, he would walk briskly as if he is descending down a slope. When he would turn, he would turn to face with his whole body.
Whoever unexpectedly saw him, would stand in awe of him. And whoever accompanied him and got to know him would love him. And those who described him would always say “I have never seen anyone before him or after him, who was like him”.
(Mashqat Shareef, Vol 5, no 373)
To summarise up, the physical characteristics of the Prophet were:
Skin Colour/Color - light brown
Hair - Neither Curly nor Firm
Stature - Medium Build, Broad Shoulders
Face - Slightly ovalish
And Allah knows best.
(For more evidence, see https://m.youtube.com/watch?v=udjM4dBVicE&t=13m45s)
Source: lifeofprophet.com and Islam Q&A