How do you incorporate 2 cultural influences into a painting? ?

It depends on the painting. Some ways are by...

1) adding a certain type of clothing from that culture

2) I don't know if this would count, but you could paint your painting in the style paintings are/were painted in the certain culture

3) add certain foods from a culture

4) add games/activities from the culture

5) add certain objects fe m the culture (ex: a phone if it's American culture)