The phrase "stick to something" is correct and can be used in written English.
You can use this phrase to indicate that someone should remain loyal to an idea, task, or activity. For example: I know you're feeling discouraged, but try to stick to your plan and you'll eventually get the results you want.
At first I thought, 'Oooweee, this ain't gonna last.' In my experience, people don't stick to something for long.
All the same, if you're seeking the perfect aeroplane meal, it's best to stick to something with a particularly strong taste.
Giving them the first few words can kick-start things for them (stick to something open-ended such as "I see/smell/feel/hear…." rather than something more constraining like, "I like this painting because…").
So you shy away from any future behavior that could undermine your expected positive feedback, turning away from difficult challenges because you are more likely to be praised if you stick to something that you know you can accomplish.
If we stick to something close to that ratio of targeted killings to targeted kindergartens, we have a chance to prevent Yemen from becoming an Al Qaeda breeding ground.
On the other hand, maybe the trick is to stick to something beneficial, un-addictive, cheap and easily available, which imbues super-strength and comes in very handy when there's a dolmen needs tossing at a Roman legion.
We do this despite knowing that sticking to something takes discipline and patience.
Pointedly, Gaydos doesn't attempt a Ritter likeness, sticking to something closer to his original design.
"Try, test, learn, and modify" is a better approach than sticking to something that isn't producing results.
With corporates, she advises sticking to something you know well.
"It gets him into situations where he sticks to something longer than he should".
