Advice to DJs, in no particular order.

-I've seen thousands of DJs make this specific mistake: playing the music they like as opposed to playing the music the audience likes. I've seen Turkish DJs play Turkish music in Korea, to an audience that was leaving very quickly. I've seen Nigerian DJs play African music to a French crowd that was leaving very quickly. And I've seen French DJs play French electronic music to an Algerian crowd that was leaving very quickly.

-In sum, my advice to DJs is simple. Know your crowd, try to guess what kind of music they listen to, and play the music they listen to.

-First variable is age. How old is your audience? Born in the 60s? 70s? 80s? 90s? 2000s? If they were born in the 60s, you want to play hits from the mid-70s to mid-80s, along with huge hits from the 90s and 2000s. If they were born in the 80s, you could play a couple of huge hit oldies, but you want to play hits from the mid-90s to mid-2000s and the huge hits of the 2000s and 2010s.

-Second variable is ethnicity. Are they Korean-Korean? Korean-American? French-French? French-African? French-Algerian? French-Egyptian? Is the group ethnically diverse? Let's say you're at a wedding between a Korean-American and a Jewish American for example. The Korean-American was born in 1989 and the Jewish American was born in 1990. Parents are Korean and Israeli. Family is Korean, Korean-American, Israeli-American, Israeli-Israeli. Crowd is mostly Jewish and Korean, with a few Caucasians in the mix. What kind of music are you going to play? Look for a couple of Korean oldies, huge, huge hit songs from the 1970s and 1980s. You want to play three or four of those songs. You want to play 3 or 4 huge Israeli hit songs from the 70s, 80s or 90s. Then you want 80-85% of your songs to be American hits, because that's what your crowd grew up listening to. Don't play “Jewish” music or “K-pop” or you only want very few of your songs to be in that roster.

-Third variable is the group that invites you or what reputation your house or club has. If you're a jazz club, play jazz. If you're a swing club, play swing. If you're a heavy metal club, play heavy metal. If the crowd you're catering to is a group of skaters who like listening to ska and death metal, play that.

-Important point: you want to ask guests if there a particular song they want to play for the occasion. But only take 3 or 4 recommendations, and space them out. A lot of times the recommendations are personal and often don't match the group's tastes.

-To sum up. Know the group. Play music they are familiar or very familiar with. You can throw in a couple of songs they are not familiar with and see how they react to those. At best they will take a break from dancing. At worst they might start talking to each other, or perhaps they will dance to that unknown song.

-You can play a couple of songs that are your creation and see how the crowd reacts to those. Don't expect very enthusiastic reactions.

-You can play a couple of songs that you really like but people are not familiar with, but don't expect crazy or enthusiastic reactions.

-Finally, hit songs are what work best. Compile a list based on the age and ethnicity of the group, look for songs that have hundreds of millions, or tens of millions of views on YouTube.

-Final tip: make sure your music is party music. Sentimental music or protest songs don't have their place at the club, wedding or party.

-Final, final tip: If the atmosphere is somber, play a huge hit. Despacito always works, so does Gangnam style, in some cases the Lambada or the Macarena works. Once people are back on their feet and dancing, you can play lesser-known (but still famous) dance hits.