The 18th century Indian painting of Maharana Amar Singh and others watching musicians and acrobats utilizes the two most basic of visual clues for applying depth on a flat surface. They are .

Overlapping.

Explanation:

'Overlapping' is demonstrated as the art form in which one object is placed over another simultaneously. This method is employed in two-dimensional artistic expressions to add depth and intensity to the work.

As per the question, the 'visual clues' that have been applied to inculcate depth onto a flat surface exemplify 'overlapping' as the pictures('musicians and acrobats along with the King Maharana Pratap') are placed over one another to provide illusionary depth into the painting that makes it more appealing and eye-catching which enhances the artistic expression of the work. Thus, 'overlapping' is the answer.

well seeing i am an artist and i actually did a self portrait; i will describe how i painted it.   i used acrylic on a stretch canvas about 4 feet wide by 6 feet tall. i painted myself smiling in a soft pink long dress, white tile floor sitting on a white couch with a table behind and a vase of gorgeous flowers.   i also had a round white hat with a soft pink ribbon through it laying on the floor and on the table behind me was a lit candle. i kept it simple but soft and romantic.