Pick which fields to use for content I have content type = CD.
As there are many fields to describe each detail (artist, publisher, performers, band, producer etc.) i want somehow to give user option which field to pick.
Of course this works by default, but i would like some kind of checkboxes in block for example when adding node, so user picks only 3 of 15 if he wants, and then 

If CD is compilation or you have many artist (Opera for example), user will proly use all fields, if CD is one man band he will use far less.

I hope i gave good explanation of what i want to acchive.
I'm not aware of a simple way to provide checkboxes of what fields you want to show for a node form.

You could probably use Conditional Fields to show 1 field type you create called desired_fields it simply has checkboxes for artist, publisher, performers, band, producer, as they check those boxes you could have a condition in Conditional Fields that Shows the field in the node form.

If you're comfortable coding you could probably have a custom form that gets the choices you want and then shows the form.

Both approaches will get complicated if you have required fields.