Started playing leona because i thought she was very similar to jarvan and very usefull to a team, and because of it i started to try to get the way of playing her. Leona is a really fun champion to play, and i hope after you seeing this guide you will give it a try.

Flash - Flash is a very good spell to initiate or to try to catch players out of position because the combo of leona can really isolate a champion and make your team get kills.

Ghost - It's a nice spell, but i do prefer flash over this one.

Teleport - It's a good spell for even to get back to your lane if you think you are going to have a hard time, or it can be used to set up ganks.

Exhaust - This is a spell i like to use too, it's really hard to choose between this one and ignite, exhaust it's a great spell and really combines greatly with your skills. since it will help your team in teamfights aswell, shutting down an ad carry.

Ignite - Many dont expect leona to kill but with the combo of ur skills and the ignite you can surprise many players with your damage output, a really good spell to get on leona.

I really like to build leona really tank, even people tell me that every champion needs to have some damage so he won't be ignored in a teamfight. Well i like to build leona this tanky because in a teamfight i can go in and really harass all the carries, and put them off the batle or of course get my team to kill them with all the combo combination, this way the other team will focus me making ad carries losing hp while atacking me(if i have Thornmail) and get them low so my team can knock team out, while i am almost full hp, because of the tankyness and the status that the W spell Eclipse gives, it almost turn impossible to them to make me any damage.

First item

Doran's Shield - I like to start with this item because it gives some health reegen, HP, and armor. With this armor you should try to harass early game and get the control of your lane early game, denying the other player any creep kills. I tried the philosopher's stone build and i really coulnd't harass the other champion, with this one only gives you the capability to stay in lane for long, but i prefer the one where i take control of the lane and deny the other champion.

Boots

Mercury's Treads - Choose this boots if the other team has alot of crowd control or too many magic damage.

Ninja Tabi - Most of the times if i am solo top and if i am being zoned by the enemy that is an AD i often choose this boots, even if the the enemy team has alot of crowd control, and then mid/late game i sell this boots and i get Mercury Threads.

Ionian Boots of Lucidity - I've seen leonas building this boots, i dont personally like it, but it still a great choice, it gives CDR, like i told before you can always get this item early game when you dont have any CDR, but when you get some tanky items that give you CDR, you can always sell the boots and buy another ones that fit more to the game you are in.

Tanky items

Aegis of the Legion - I like this item because it adds to the status that your W Eclipse gives and makes you more strong and tanky. This is a good item too because i like to tank so, this item provides buffs to me and also to my team wich will make my teammates a little bit more durable while i am ganking and make us have some extra advantage while doing so.

Negatron Cloak - Offers a good amount of magic resist, makes you tank magic damage.

Chain Vest - Offers a nice amount of armor, for you to be able to tank some atack damage from the other team.

Warmog's Armor , Force of Nature, Thornmail - This three items i choose depeding on who of the other team is doing the most damage and who my team needs me to tank more. So this items order of buy change game to game you have to adapt them to the other team.

Frozen Heart - It's a really nice item, since it gives some trouble to those ad carries trying to kill your team. And it gives a nice amount of armor, mana and CDR.

Shurelya's Battlesong - It's a nice item since it gives all bonus leona wants, CDR, Hp regen, mana regen, and gives a nice chasing or escaping bonus. This is a nice item to get over Thornmail (if noone of the ad carries is shredding your team appart), if you feel like some opponents are getting away always with so low hp, and u need a boost on speed just to make that last hit or towerdive, go for this one, it really helps. I've seen many leonas building this one in the begining, because they start with Philosopher's stone and they imediatly go for this item, that's not a good item choice, if you like to build this item earlier in the game go for Aegis of the Legion first it gives you more tank status, and then go for Shurelya's Battlesong then this way you now can towerdive/chase more safely because you already have a nice magic resist,hp, armor, same as cdr,hp regen and mana regen.

Pros:
- She has tons of Crowd Control
- Has a good initiation
- Very Tanky
- Great combo of her skills
- Great ganking abilities

Cons:
- Hard laning phase, need to be solo lane to get more viable late game.
- Her damage is a little weak.

It could exist more cons but i dont think she has them, until i am proved otherwise.

While in the laning phase, i usually try to provide my team the most ganks i can make.
I usually play her top solo lane, and when i push my lane or even when i go back to buy items, i try to get some ganks to my team, most of the time i do them by myself, but it's really good if your jungler gives a little help too, most of the times the ganks i provide are almost garenteed a kill.

When i gank the most is after i get my ultimate Solar Flare, when i have it off coldown, i always try to use it to provide a gank.

While in the laning phase try to push the minions with ur W spell Eclipse, and farm with it, then if your lane is pushed it's like i told you try to gank, otherwise keep farming.