Well, basically Lee Sin support is kinda like Braum, Leona or Thresh support. It requires alot of mechanical plays but if pulled off well, you can definitely peel for your adc/apc or protect your adc/apc with your kick.

My IGN is DontCryNoob from Oceania server. My main is support and when I learnt how to play Lee Sin, it was horrible. So I integrated the standard support build into the lee sin and train my ward hops and mechanics

Well basically pros of this hero is:

Very good early game damage
High Mobility
Can knock up multiple enemies using Dragon's Rageif they are funneled during the fight
Very tanky at late game and can definitely maneuver to the backlines of the enemies easily

Cons?:
Very Mechanical
Requires good team to follow up when you peel for them
Low damage at late game

Basically I choose to max the Utility tree as it gives quite alot of gold during the laning phase. Also the movement speed increase is good for roaming and helping your jungler to invade. You could choose a standard 0/21/9 tanky mastery build but for a Lee Sin support, you definitely need the utilities to farm up a storm

Item notes:
For beginners try to on smart cast and turn on range indicator. Therefore, you can see the range of the wards and your Safeguard. When you become better, you can remove your training wheels and turn off range indicator.

Item orders.
Well in order for Lee Sin or a support to be useful, try to rush your Sightstone and swap out Stealth Ward for a Sweeping Lens. This allows mechanical plays and "insec kicks" to occur.

If the enemy team has a heavy AD team, rush for a Randuin's Omen and get into the middle of the action.

Likewise, if the enemy has a heavy AP dmg, go for Locket of the Iron Solari. This allows you to not only boost your own magic resist but also boost your teammates magic resist.

Towards the late game, aim for Banshee's Veil as this prevents you from being caught out by a cc effect such as Morgans Dark Binding. However, if the enemy adc or AD are shredding your team, go for Thornmail as it will return some damage to the adc. But on average, I will build a Banshee's Veil as late game cc can be quite a pain.

Skill sequence:
I'd recommend maxing E Tempest because of the slow. However, if the enemy had a heavy poke com / cc, I'd suggest maxing Q Sonic Wave. This allows you to deal a lot of damage and immediately safeguard to your teammate.

During a fight, there are many Lee Sin combos which you can view on YouTube but the most important one for a Lee Sin support is kicking the enemy to your teammate during a fight or trying to hit multiple enemies when running away.

Note for lee sin beginners:

These are very mechanical and requires training. But then again, a support doesn't really need to CS a lot, therefore, you can just ward hop around and fool around to practice. Bear in mind, it took me about 5-10 games to master ward hopping and kicking enemy the right direction during a team fight. Don't be embarrassed and try to practice in a normal game :)

Tips?
Well the only tip I could give you is try range indicators and if at some point you feel its slowing you down, its time to remove your training wheels and go on without range indicators. With smartcast, it'd definitely allow you to ward hop faster

The only CS you should be getting is the kills with your charges on the Relic Shield/ targon's brace/ face of the mountain. The thing about Lee Sin support is your Q Sonic Wave allows you to CS from afar and also healing your adc. Try to aim for siege minions as they give more gold.

Your E Tempest allows you to hold a minion wave well as you can slow the wave from approaching the turret.

If you are getting better, you could help your jungler to counter and also farm some small monsters.

For teamwork, it is important for you to follow your jungler movement. Always try to help him and if he is tanked, try to help. Also, if mid lane is getting out of control, try to help your jungler and mid lamer by ganking them.

Lee Sin coupled with an Elise is a great dragon killer. When you and Elise are lvl 3, you two could easily take down dragon. However, bear in mind the position of the enemy jungler and wards in the dragon pit. That early dragon allows you to rush sightstone.

To many this may seem like a troll guide, but Lee Sin support is really good if played properly. He is equivalent to Braum but way more mobile. Then again, enjoy the game and even if you fail, don't worry, you are essentially training your lee sin mechanics and eventually you can be a good jungler with him.