By getting only very slightly drunk.
Seriously, as has been said, there’s really nothing you can do to speed it up.
You get sober as your body processes the alcohol.
The average liver processes 1 unit of alcohol (1 unit, not one drink) per hour. As an example a pint of 5.2% beer is about 3 units.
How quickly your body processes alcohol can vary based on a few factors (weight, gender, if you are taking medication, how fast your metabolism works in general etc) but 1 unit per hour is roughly correct.
So 12 units of alcohol would take 12 hours to leave your body.
Over the years I’ve replied to quite a lot of questions asked on Quora. I thought I’d post some of them here. I’ll post the reply I gave at the time and I won’t edit the original answer unless they are very embarrassing 😉 or to fix typos, but I may add an update or correction as a reply if needed. Please feel free to add/disagree etc in the comments section! This answer was originally posted on Quora on 5th May 2019.