I want to say I'm good at something

[alpacinou]

I want to say I'm good at something, for example solving crosswords.

Can I use "I have a good head for"?

Is this correct and natural?

I have a good head for solving crosswords. I usually finish crosswords faster than my brothers.

If that doesn't work, what other idiom can I use?

 

[Tdol]

It's OK. You could also drop solving.

 

[Phaedrus]

. . . what other idiom can I use?

Another expression that you can use is "knack for":

I have a knack for (solving) crossword puzzles.

 

[Tdol]

You could say that crosswords are your forte.

 

[emsr2d2]

You're a crossword demon!
You're a crossword ninja!

 

[tedmc]

I am an expert at crosswords.
I have a flair for crosswords.

 

[alpacinou]

Can I use "have a good head for" in music?

I have a good head for playing the guitar.

 

[emsr2d2]

That doesn't work for me. Playing the guitar is a dexterity and musical ability issue. Having a good head for something usually suggests a level of intelligence or intellectual ability.