This advice is taken from this thread and other similar ones on this site.

Quote Originally Posted by Thor
we agree that the best way to make sure that you've actually got an Instinct is to put it in an If/Then statement with specific mechanical effects.

So: If I see a dead body, then I Assess.
If confronted with combat, [then] I assume Aggressive Stance.
If there's a cave-in, then I Push the youngest to safety.

You can use Always or Never statements as well, though you have to be careful with these and make sure that you are describing a mechanical effect:

Always cast Facets Carefully and Patiently.
In the deep tunnels, always Assess (listen) at every junction.
At the first sign of combat, I always Draw my knife.
Never Work Quickly.

If you always make sure characters' Instincts are tight and narrowly focused, two things will happen: one, it will be easier for players to use those Instincts in play, and two, it will be easier for you to incorporate conflicts where those Instincts generate complications for them (and thus allow you to award them Artha).
"So instincts are action-oriented macros?" one querulous gamer asked.

To which, Thor offered, the theory behind it all, so eloquently put:

Quote Originally Posted by Thor
Absolutely, that's one level. I think of that as the Mechanical level.

In a way, what the BITs really do is help the group to establish the Social Contract.

At the mechanical level, my Instincts establish with the group that "my guy" functions in a slightly different way than the baseline rules. He's so aggressive that he actually starts combat in Aggressive Stance, even though other characters have to take an Action to do that.

Or, he's so cautious in the deep tunnels that he Assesses at every junction, even if I don't actually state that when it comes up. In fact, that's so important to my character that if we all forget and suddenly turn a corner and run into something dangerous, we'll back up a step so I can roll my Assess to see whether I became aware of it.

Then there's what I'll call the Character level. This works on the principle that "Actions speak louder than words." Instincts are the most primal, compact way of telling everybody at the table what your character is about. Sure, my character has a few Beliefs that do that too, but those are more of a big picture thing. If my dwarf has the Instinct, "If there's a cave-in, then I Push the youngest to safety," that tells the entire group a lot about who my character is and what he values. First, he's careful and aware of the dangers that come with being underground. Second, his first thought is to protect someone else, not himself. And third, that someone else is the "youngest" meaning that he puts some sort of value on youth (and the group might rightly come to the conclusion that since he's the oldest dwarf in the group, and has taken the "Husband" lifepath, that this Instinct stems from a desire to protect children).

Finally, there's the Story level. On this level, the Instinct is a direct statement to the GM, "I want to showcase this aspect of my character." If I have the cave-in Instinct, I'm telling the GM that I want at least some of the game to happen underground in caves or tunnels, and I want to have a cave-in.

Anyway, that's Instincts as I see 'em.
And that's how we see 'em, too! I swear Thor's been reading my notes!

To reinforce Thor's point, and to quote the master himself in this thread:
So sayeth Kublai: Specific actions to specific stimulus.

For example: How do you give your advice and what event triggers your speech?

How do you protect wounded comrades from harm? What defines harm? Do you see the abuse that's possible here? Harm can be defined as a sword strike to a falling rock to making a faux pas at a ball. Ways to protect comrades are equally undefined. That's too much ground for an Instinct to cover, really. In combat, perhaps "If a comrade is wounded, then I step between him and his opponent and block." Even this is really pushing the limit.

There's good instinct advice from Pete/Kublai in this thread.

And you can find examples of his own character's instincts here

- Taste food before serving or eating.
- Always have enough ingredients for noodle soup.
- Keep wok securely tied to my back when traveling.
and here

and here

I hope this has proved helpful.

If we see one more Instinct that is a Belief we're going to rewrite the damn game. Oh. Wait.