Lord Ganesha or Omkar is the basic form of nature according to the Hindu Philosophy and it is a known form of all unknown or unexpressed total universal divine knowledge. Om is the original root cause of the universe and all the things of the universe are the sound waves in nature. (OM) is made up of syllables 'a' + 'o' + 'm' and it stands for the Hindu Triad (Trimurti), Trinity of Gods, consisting of Brahma the creator, Vishnu the preserver, and Shiva the destroyer as the three highest manifestations of the one ultimate reality. Letter 'a' refers to Bramha. The letter 'o' refers to Vishnu. The letter 'm' refers to Mahesh/Shiva.
The combination of these three symbolic Letters/forms makes OM as Lord Ganesha. It means worshipping Lord Ganesha is like worshipping these all three gods, the incomparable everlasting total universal divine knowledge. I found three primary colours Yellow, Red & Blue are appropriate for this painting as the whole world of colours get created from them.
*This original painting is 2.5ft x 2ft. My white watermark will not exist on the painting.