What I mean by a "spiritual hack" is taking some thought/action/belief that is originally grounded in a religion or mystic school of thought and repurposing it for your own daily, and selfish, use.
The first one is a biggie, and it can be immensely useful in transforming mundane tasks into great epic works of timeless import. The sign of the cross is great because it's not overused in the media, you don't see it much in public, yet everyone still knows what it means. It has a great weight to it.
There are two main ways the sign of the cross can be used: 1) to bless yourself and 2) to bless other stuff. Whichever one you choose will depend on the situation.
You may be thinking to yourself, "Come on, I don't wanna waste my time doing some little hand thing. I just wanna eat my taco."
But think how much better that taco will taste once you've given it a one-handed hit of the holy. It's way more fun than it sounds. And it doesn't matter if you're a spiritual person or not. In fact, it's probably more fun if you're not. It'll give you one of those spiritual connections everyone's always going on about but minus the whole belief thing.
So yeah, start small. Start with that taco. You can add to the ritual if you want: vestments, chants, big hats, whatever you have around. But don't oversell it, there could be Protestants about.
Now unwrap the taco, give it a look to make sure there aren't any hairs, and then whip out the blessin' hand. You might not even need hot sauce. But if you do, might I suggest flicking it onto the taco from a distance of 6"-8", à la holy water.
Yeah you might feel stupid at first, eating some anointed taco, but think about the wicked awesome tapestry that's being woven in your honor.
Not long after the taco, you may feel the need for a bathroom excursion; practice session number two! To be safe I'd bless both yourself and the toilet. Before and after.
Isn't flushing more fun when it's a septic rapture?
The more you do it the more you'll start finding (or investing, whichever) meaning in every little thing. Have an important email to write? Bless the keyboard. Had too much to drink at the bar? Bless the cabbie who gets you home. Sure he might think you're a serial killer, but hey, he could be one too. Can't be too careful.
Go nuts tomorrow! Bless yourself before you get in the shower, bless your car before you drive to work, bless the morning coffee, bless the Powerpoint presentation, bless the lunch you eat too quickly and ends up giving you a stomach ache. The smaller and less important the better.
But do try to avoid overdoing it in the long run. The worst that could happen is it becomes something you feel obliged to do. What's the fun in that?