senin için evleneceðin erkek nasýl býrý olmalý

My try: 

How would the man whom you will marry be ?

 In your opinion what kind of a guy should be the one you will mary ?

For you how a person should the man you will mary be ?

k_s  I liked your sentence much than my attemps. but adding "in you opinion" or "for you" should be considered. Do you agree?

great translations. Thank you everyone.

 Yes, i agree with you.

I have forgotten "senin için" to translate.

Thanks

And my simplified English attempt is:

How should your future husband be for you?