69, what a passion. It can look to some like a tricky or acrobatic position, but I guarantee you it is not (in most cases. Then if you're gonna do it in vertical, I suggest you try to get a job at Cirque du Soleil!)
For us women it's the empowering, feminist version of the classic fellatio.
The simple fellatio has been for years and centuries just one of the most important duties of a wife, intended only for the men's pleasure. I am sure I can say in most cases it has been even currency, or at least it has been bartered since the human beings live on Earth. But the 69 finally introduces the great unknown: the female pleasure! Thanks to this amazing position, giving oral sex to your man is no more for his pleasure only, but for yours too! Then there are plenty of us that give fellatio just for the arousing that comes by giving it, and they're welcome too!
The 69 helps you if your man isn't so comfortable at the idea of giving you a nice cunnilingus alone: he will be so concentrated on his pleasure, and he has your beautiful pussy right in front of his eyes: chances are he will lick and suck without thinking about it twice.
It can lead you to powerful synchronized orgasms that are the dream of every kinky couple. Who doesn't love that magic of when you both cum at the same time?
Last but not least, there is the adventure factor: 69 just brings that feeling of unusual position and the excitement that comes with it. Bye bye, missionary!
So what's my advice for the best 69 of all times? The bottom person should lie in a comfortable position before the top positions himself/herself over, I think the best for comfort is doing it on the bed. When the top is tired of staying in that position there should be a switch with the bottom. Add a nice flavoured lubricant and...have fun!