Sorry no magic here. The only cure for jet lag is time, and we humans adjust by about an hour a day.
I don’t know about you but I have read volumes about jet lag trying to find a magic bullet. The thing is that if you have commitments in your regular time zone there is only so much pre-adjusting you can do.
So what I do is plan for it.
Embrace the sunrise
I am not a morning person, or a night owl. I have a few good hours in the middle of the day. What this means is that I rarely see sunrises at home. The greatest thing for me about jet lag is being able to great the sun as it rises and take advantage of the early morning light for a walk about.
Organize the trip to make the first few days easy on you
If I know I will need my wits about me I plan ahead. Visiting Ireland we stayed the first 4 days in Dublin at one place and used public transportation before picking up a rental car and needing to remember to drive on the left.
That worked better than our much shorter trip where we picked up a car at the airport and headed out immediately.
Add a few extra days to the beginning
When I need to have my wits about me I add a few days to the beginning of the trip. In this world the most adjustment you need to make is 12 hours, so three days = three hours is a decent percentage of any adjustment you need to make. Being outdoors in the natural sunlight and being physically active are two features I look for to jump start the adjustment.
On my two trips to Mulundi village in Kenya I felt like I really needed to have my wits about me so I added a couple of extra days at the beginning of the trip. The first time we took them in Amsterdam. We just wandered about.
The second trip I splurged (it was a major birthday year for me) and took a three day safari to Masai Mara, where jet lag was an asset, I enjoyed being fully awake on the early morning game drives. Spending the days outside in the sunshine watching the amazing wildlife was a great way to get my internal clock adjusted to the new time zone.