Heritage roses came from many parts of the Northern Hemisphere. They developed in a wide variety of natural environments and consequently they have quite different requirements with regard to their care and maintenance. In particular they should not all be pruned like the ubiqitous hybrid tea. Each group have their own growth habits and therefore need corresponding annual care and maintenance.
Find more hints on pruning the heritage varieties here.
Climbers by their very nature want to reach for the sky and inevitably do not flower until they have reached the top. Most have rather thick canes, which resist bending, unlike ramblers. It is very difficult to study a rose or smell the perfume standing on a stepladder. So we must fool the plant to give us blooms at a lower altitude and yet have it reaching the top of a festoon, tripod or arch.
During the spring and summer, let the young climbing canes go as far up in the air as they can. Preferably the height reached should be the distance required when the cane is brought to the horizontal. Many climbing canes will not increase their length once they are trained to the horizontal. In autumn, take the long canes and gently bring them down towards the horizontal without stressing or breaking them and tie them at that angle. The canes should end up as close to the horizontal as you can get them, which may take several weeks of tying, then re-bending and re-tying to get them there.
Canes of climbers do not like going downhill, frequently suffering dieback in these attempts, so do not attempt to take them below the horizontal. In your home garden you can bring the canes down by tying an old soft drink bottle to the end of the cane. Add water to the bottle every couple of days to increase the weight until the cane gets to where you want it. Having tortured the canes into these new shapes stand back and watch laterals shoot up from almost every second bud. These laterals become the flower bearing shoots.
For recurrent climbers, deadhead the laterals fairly firmly (back to a plump bud three or four from the main cane) to give best displays of roses. In winter pruning, try to replace old non-productive canes with new young canes. For non-recurrent climbers, summer prune the laterals to the same level of two or three from the main cane, doing a shaping trim only, during winter. For best effects on a tripod or post, wind the canes around the tripod or post at about 45 degrees to the horizontal. This will entice the climber to throw laterals along the climbing cane and give roses at a lower level.