Some dog owners believe that a dog is a dog, and that his place is on the floor exclusively. Some feel that he is a member of the family, and that he should be allowed up on chairs or sofas if he feels like it. And there are attitudes in between that may dictate permission for him to get up on one "favorite chair." Generally the split is between country and city, with country dogs being relegated to the floor and city dogs having the run of the place.
If he is going to be strictly a floor dog, then he should never be allowed up on any piece of furniture, right from the start. Being up on the couch with you or solo hold little distinction for him and it will only confuse him later if you deny him the privilege. When he is little, he won't be able to negotiate the height, so there is no problem with him climbing up.
As he grows and investigates, he will try to climb up just to see what is there. Push him off gently and tell him "no" a few times and he will get the idea. Later he may try to occupy it while you are out of the house. An easy solution to train him is a few light mousetraps covered with a sheet or newspaper set near the back of the cushion. The trap can't hurt him and the snapping noise will solve the problem.
If you decide that he is going to be a full member of the household with all privileges, the problems are only those of dirt and reactions. As for dirt, he should be trained to wait at the door for a quick cleaning with an old rag after he has been out of doors. By the time he is old enough to climb onto chairs easily he will be old enough to have learned the "sit and stay" and there ends the problem.
As far as reactions go, this is really something between you and your friends. Somewhat fastidious friends who come to visit may find dogs on furniture disagreeable, particularly if the dog has to be shooed off of the chair they are about to sit in. If he is a chair sitter in your house, he may try to be one when he goes visiting with you. So set up a rigid rule for him - okay at home, forbidden elsewhere, and don't make exceptions and he won't be likely to be confused.
Randy Jones and his partner Brent Jones have been in the pet industry for a long time. Recently they formed Joncopets.com. On the site, customers can read articles about anything pets as well as shop for the latest dog collars and more for their best friend. Feel free to check out the site at http://www.joncopets.com.