My other builds:
Garen - A DPS Hybrid Carry Build
Taric - A Tank/Support Hybrid Build
Morgana - An Archangel's Staff Exploit Build
Ezreal - A Flexible AP/AD Hybrid Build
Note: This is not a guide for how to play Galio, simply a build to utilize in conjunction with those guides.
This build was written shortly after Galio was introduced, so as the LoL community begins to understand Galio better, the situation may change greatly. It is with this in mind that I introduce to you my Sunfire/Magic-Resist-stacked Galio tank. One of the main features of this build is its high magic resistance and armor, as well as its two Sunfire Capes. The Sunfire Cape goes well with Galio as not only do they raise his survivability, but they also help him become much more of a threat to the other team. The Sunfires can also help do damage to enemies while mid-chase, something else Galio excels in. The early Chalice of Harmony helps Galio with some mana problems he may have because of the lack of caster items in this build. I chose Clarity as one of these summoner skills because of his possible mana problems, but if adept at using Galio and managing his mana, one can choose Ghost or Cleanse as an alternative summoner skill. As Galio is highly vulnerable to disables and interrupts as they stop his AoE taunt skill, Idol of Durand, therefore the Banshee's Veil between the two Sunfires is crucial for Galio, and may change the outcome of a team battle. Finally, the Force of Nature as his final item will improve his survivability as well as further boost his ability power with the help of his innate skill, Runic Skin.
Keep in mind that with this build, Galio will excel greatly in tanking casters of all shapes and sizes. However, he may not fare as well against strong physical carries, unless his Bulwark and Idol of Durand are active. That being said, he can still tank most physical DPS and initiate without much difficulty using this build.