This is my first guide and my english is not so good, leave a comment at the end

Magic pen mark: in early game i do a little bit more dommage
Armor seal: indeed it's tank build
Ability power/lvl glyph: do more dommage in early game
Flat heal quint: more durable in early game

I buy regrowth pendant with a mana pot in first, that let me be more durable in lane to get enough gold to b buy philosopher stone and boot, no need to get more mana/heal pot cause philosopher stone lend you a good healt/mana regen/5sec with a little gold bonus.
After, depend if my opponent are AD(noct/akali/teemo) i get thornmail, if they are AP(ashes/caith/ezreal) i get force of nature first.
Frozen heart can be switch by Randuin's Omen
Sunfire Cape can be trade for Banshee Veil's

I begin with sapling toss cause of his capacity to be an "explosive ward" and it's very a good harrassing spell, i master sapling toss frist
At lvl 2 i get twisted advance for his stun ability and i master at lvl 9
Lvl 3 Arcane smash 1 point and i master in the end
For Vengeful maelstorm i put a point when i can