The attributes of wall combos, like most things in Tekken, have a considerable amount of depth and nuance. Because of this, it can be difficult at first to maximize the damage potential from them as a new player.
If getting the most out of your wall combos is proving a little difficult right now, I highly suggest trying out Lars. As JusticeSoulTuna demonstrates, Lars has great wall carry, and one of the easier wall combos in Tekken 7. What you learn here can also transfer to other characters, and your damage will be better for it.