Terraria: How to summon and defeat Plantera

The hardest part is honestly FINDING Plantera's bulb (Pink little bulb... when broken with anything but an explosion summons plantera).

You have to defeat all 3 mechanical bosses and HAVE some sort of intact underground jungle (Natural or artificial both work). Not easy when the corruption/crimson often takes the jungle in it's spread. So a chlorophyte farm which doubles as an arena for dealing with Plantera does wonders. Same farm also allows you to get life fruits which spawn after any 1 mechanical boss have been defeated. The key is jungle grass surfaces and a 2x2 clear area is required. And an overdoes of patience. Given that said bulbs won't spawn next to each other... yea.

AFTER this has been done (and waited!). Once you are ready... destroy that bulb with a pickaxe of choice. Assuming that you are with gear related to progression, the best armor is dependent on what class you are. By this point you will know what class suits you best.

For rangers: Go with chlorophyte armor with the helmet. Frost armor also works. Weapon wise depending on preference, megashark/uzi (rarer than megashark though) or chlorophyte shotbow/hallow repeater with the best modifier you can afford. The Clockwork assault rifle works too (Farm WoF if you want but the megashark is much easier to get).

For Melee: Turtle armor will do (just kill turtles in the jungle to get turtle shells). Frost armor is a good choice too if you can get the RARE drops required to make the set. Good weapons are the shadowflame knife (Farm the goblin invasion in hardmode), Death sickle (if you got lucky and survived a solar eclipse the reapers have a chance of dropping the death sickle) being one of the best choices, Yelets (the yoyo) is good too and is a rare drop from jungle enemies.

For magic users: Yet again, chlorophyte armor with the headgear. Weapon wise go with: magical harp (Crafted), magic dagger (Hallow mimic drop), Nimbus rod (if you can get the rare item!).

For summoners: Spider armor is the best bet. Yea at this point good summoner armor is lacking. Weapon wise: Optic staff, Queen spider staff, or spider staff.

Accessories:

All: Wings + Speed boots (Required), Charm of myths (Reduces potion cooldown and boosts health regen), bezoar (immunity from poison is very handy, this is optional), cross necklace (really nice for reducing damage taken), Star veil (boosts damage when you take damage), Flesh knuckles (For those who will take lots of damage like melee), avenger emblem/respective emblem (Really nice to have!), worm scarf (Damage reduction is always good to have!), etc. Mana flower is good for the magic users.

Potion wise: Best healing potion you can get and a full stack of it, Ironskin, endurance, regen, wrath/rage, respective damage boosting potion (archery/magic), best mana potion (for the magic users in general), any potion that will help you really.

Stay on the move in the arena! Of course the arena should have the standard health regen boosting stuff (heart lantern + campfire does wonders). And lots of space (duh). If your weapon has autofire/autoswing, keep spamming your attack of choice (Gun/magic/melee). For ammo (Rangers only) go with chlorophyte bullets if using a gun (Paired with the megashark you won't use up so much ammo. The ammo reservation potion helps a LOT!).