How do I get my paper sent to the right editor? Suppose I have found the perfect journal for my manuscript.  That journal has 50 editors.  Editor A is an expert in the subject of my manuscript.  What can I do to get my paper handled by Editor A, instead of one of the other editors?
This is going to depend on how the journal is set up, but two suggestions:


Suggest in the cover letter that Editor A handle your manuscript.
When asked to classify your manuscript choose keywords that closely match Editor A's expertise. (You probably are doing this already anyway.)


Note that it's not a guarantee that Editor A handles your manuscript even if he/she is perfect for the role - it's conceivable Editor A is too busy, is on holiday, etc.