You could substitute in the word "initiative," "goal," or "target" if you don't like mantra. I'm not a believer in anything new agey or mystical. Rather, for me, "mantra" captures a complex and detailed idea in a short word or phrase. They're things I'm working on.
I was brainstorming at a cafe what I'm working on, what's most crucial in terms of development. This is the list I came to -
Start day productive
I don't need to feel good to do the right thing.
In greater detail:
Create: Make things that didn't exist before, for myself and for others. This is higher level work than what I'd call "Maintenance," which just keeps you afloat where you're at. (Maintenance is still super valuable though, I do a few hours of maintenance a day. Stretching, answering email, and doing basic responsibilities of a typical job would all be maintenance.)
Enterprise: The hardest to explicitly define in words, but not difficult to grasp. This is roughly getting people to use what I create, and getting compensated for that. Enterprising is the marketing, business, getting paid side of things. Mostly. It includes some other semi-businessy things like that as well.
Start day productive: I already spend the first 30 minutes of most day pretty well - stretching, a little planning, and things like that. But beyond that, I'd like to spend the first 3-4 hours on the most important things. That's not a particularly revolutionary idea - almost everyone agrees this is valuable. Yet, it's easy to do semi-important things or get distracted first. I find the first few hours of the day often sets the tone for the day, and I'd like to keep refining how I spend mine.
Focus: Put uninterrupted focus into tasks. Don't multitask anything that's important. If taking a break, explicitly take a break. Don't halfway take a break. This is surprisingly difficult to do sometimes, but I think it's probably one of the biggest predictors of success.
Celerity: Move faster. Celerity.
I don't need to feel good to do the right thing: I scribbled this kind of aimlessly at the bottom of the page, but I'm starting to think it's wonderful. A lot of times, I'll be tired or low energy or uncreative or whatever. Happens to everyone. "I don't feel inspired..." - and then I can repeat, "Well, I don't have to feel good to do the right thing."
It's kind of brilliant in its simplicity, and lots of value in it.
That's what I'm working on developing for traits lately. What are you working on?