With the expansion files, how do you test your build?

Hi,

Now that I got the expansion files built resulting one apk file and one .obb file, how do I install my app on my device?
What to do with the obb file? 

thanks

I test it without expansion file locally, and then for testing the expansion files I just create alpha test in google play store.

ah thank you, that makes sense

I test it without expansion file locally, and then for testing the expansion files I just create alpha test in google play store.

ah thank you, that makes sense