It depends on what sort of feelings you want to express. From your question I'm assuming that you want to tell something negative to your beloved one. May be you want to tell him/her about something that you don't like. If this is the reason than I think you should make a situation to tell about your feelings. First create a very good and emotional environment where his/her heart is melted. Start with slow and soft voice so that the person can understand you have a deep love for him/her. Make some fun and tell about some example about what you want to tell. This will make the person ready to accept what your are going to say at the end. Then apologize first that s/he might got hurt and then express your feeling softly. I think any negative minded person will also become positive with this attitude.
But if you are going to express any positive feelings like you want to make your best friend to your girlfriend or something other then go for a coffee and hold the persons hand and straightly tell her about your feelings. Holding hand of a person even if the person is a male is not a sin. It's a sign of sympathy, softness and dependents. Telling the heartiest feeling straightly is a sign of bravery.
Remember one thing and that is telling the truth straightly even it is bitter can cause distance for a little certain time but in future the result will be the sweetest than ever.