@Takis Preftitsis sure, If you’re going to make yours out of wood make sure your wood is wider than 88cm on both sides, the height is purely up to preference, but however if you want a taller bar, then essentially want to dig your hole deeper to avoid any wobblyness or shaking. For the bar it self I just used a metal pipe (spray painted for better aesthetics) with skrew attachments with gorilla glue for extra security, Each hole has about 2-3 bags of cement Also make sure to get some sort of post protection to avoid your posts from rotting from the groun. And lastly, if you want your bars to be extra sturdy then build more poles and bars connected all together, this will make your bars even stronger and last years