When you are support Zed, your main purpose is to poke the heck out of the enemy
Use your shadows as wards and use them to poke the enemy team and lower the health of the minions so your adc can farm smoothly. You can also use them as a secondary flash or a bait tool.

Participate in team fights by using your shadows, also tend to keep your distance by using your ult and W.

When it comes to your ult, use it on tanky enemies or enemies prioritized by your teammates.

Stay close to your adc so you can shield them with your rune, you can also use your rune to shield your teammates during team fights.

Use Redemption and Iron Locket to cover for your lack of heal and shields

Build tanky so you can bulk up damage

Tend to buy the most mobile boots so you can evade and ***sist your teammates quickly