Follow this build if you wanna have a good solid game as Galio.

Remember not to pick Galio before enemy team pick their mid or else they're just gonna pick a ad to counter you.

Also try to use bulwark just as you engage in combat because then when they use all their abilities on you you almost won't take any damage at all.

The last tip is if somebody as the mid lane or the jungler tries to tower dive then you just use bulwark and then your ult and you will most of the time get them both.

This was my guide to Galio hoped you enjoyed it and I might do some more in the future. :)