first what you want to do is get teir 2 of the Logos(i got mod for 2 stacks per coin)
Then after that you want to get full tier of eye of ekron (i have mod for 5% power damage conversion of bonus will) after that is filled up and you have a good amount of stacks, save up for metalo's heart. yes i know what you guys are thinking "why so much buffness for a support class?" well because i found this out from an enemy i lost too, i was wondering why he wouldnt die fast and i took a look at his items so i was able to combine some of my will/power offensive build with his tanky defensive one. you see the more will you have the stronger your shields are, infuse/siphon it doesnt matter it will protect you and your allies greatly with all your bonus will, the adiditonal attack and power armor and health in this build will make it so you can survive longer, even if teamates dead and trying to get at turrent or capture oribital cannon, you can go in and poke and delay and bug them, be as annoying as you can to the enemy because you will be a hard SOB to kill thanks to your protection and effectiveness of your shields and if you do die, and get revived by your passive, you will be revived with more health. now after getting matelos heart, fill up the rest at your lesuire. the qward gambit is great for its will, and also increase your power damage and life steal. now for your final item, if you want to focus soley on protecting yourself and teamates and you wish to live longer, get the diamond for more power armor, and power lifesteal but if you want to use your unusual tanky like build to push more and  be a more offensive support then i recomend starheart you can never go wrong with it for any power champion. i use this build mostly on gh because of easier money and starting out with, but you can use this build on any map and if you want money fast for the rest then i suggest to start with qward gambit and getting the mod investment. anyway have a good time being a powerful support with your shields as nightmare superman!