Maybe this is how Selena Gomez preps for her tours.
The "Slow Down" singer was snapped on Instagram singing karaoke with some pals!
Sel and a pal named Jivanta Roberts were on hand to celebrate their pal Darnell Applings' birthday -- that's him in the photo with Selena!
Knowing how much Selena loves Britney Spears, we're willing to bet she belted out a classic Brit tune ... but it would be pretty funny if her friends sang "Come & Get It" or "Who Says," wouldn't it?
What do you think Selena sang at karaoke? Do you have a favorite karaoke song? Tell us in the comments!