In 1929 Nikolaou was admitted into the Athens School of Fine Arts, where he studied under Konstantinos Parthenis and Umbertos Argyros.
In 1935 he became a member of the group "Free Artists" (Ελεύθεροι Καλλιτέχναι) and participated in the Parnassos exhibition.
That same year, Nikolaou came to the defense of a new artist, Constantine Andreou, whose artwork was so lifelike he was accused of cheating.
In 1937, Nikolaou followed Yiannis Moralis to Italy and in 1939 he received a scholarship to study in Paris.
A few years later, he managed to convince his long-time friend and colleague Andreou to buy a house on the island.