Okay this is only a build for maokai not full guide so I will not tell everything about maokai.

Itembuild will make you superior tanky and gives some nice mana for your ulti. Boots of swiftness are must on maokai because of he is SLOOOOOOOW. Sunfire cape and arcane smash makes you hard pusher, allows some towerdiving, and you cant handle the gold income! Banshees veil is must almost in every game, so build it next, its very usefull. I like to build up frozen heart next because it gives 500mana... This champion needs mana! and CDR 25%!!! Okay this is the corebuild. Next items should be chosen by your enemies... lots of melee?... take thornmail. Its simple. lots of magic?--- take force of nature etc etc you should know if you are not like 1-5lvl.

Dont fail building this Champion as Ap--- please it just sucks and that makes you weak.
Strong tank is always superior annoying and sooner or later they want to focus you (which is good) because you have only 1-3 deaths. Test this build before you comment...

Arcane smash rank 5 haves some nice damage so max it first... you will not need Ability power for doing some nice damage, squishy champions shall hate you.
Then rush into twisted advance rank 4... it haves rooting long enough so dont take rank 5 yet. sapling toss is only scouting tool in earlygame.... max it last.

Comment how this build works on your summoner and rate!
Burning tree is gonna bring you the pain!