I used to get Q first, but then I started to get W as the heal is overall easier to play with. You can top off your jungler if you are helping leash and can heal your ADC if they fail/trade early game. If you want to rush to level 2, though, getting Q will be better as you can "push" faster with Q's AoE damage. At 3 I get E then I max heal, as its tied to how much your Q will heal when you hit a champion + bigger heals. I used to max Q, but its harass is easily dodged and if you miss, you'll be OOM and possibly w/o HP either if you've been topping off your ADC. Also maxing heal requires you to have to heal less as it heals MORE per rank(obviously... wish I was smart to realize this earlier). Ult is used the same way as before, just got buffed for people below 40% hp I think.
In terms of laning, I harass with auto's if I can and use Q for vision/self-heal. An upside to not maxing Q is that it does so little damage people don't seem to care if they get hit by it, so free HP for you. Eventually around levels 7-9 if you're still in laning phase and things are equal, as long as they don't have a healing support, you should basically be able to win lane through sustain as any damage they do will get healed by you. Teamfight wise just heal whoever is lowest and back off when you get low, trying to be bait and to heal/CC if you can and still impact the fight.
Item wise I go start with
, 3
, and 1
. Pots you can interchange to how you play, trading more/less mana pots depending on how much you spam. First buy is
and/or
, getting the other one after when you buy one of them. After this, you should go towards
as it will solve all your mana issues. You will go OOM no matter what if you spam, so this solves that, also you will build it into
eventually. As you start roaming, after your or their bot tower is gone, get
as it helps you move around the map and get to places faster. As you teamfight more, finish your support item and that's my "core"
. Its pretty cheap and has lots of useful pieces that helps shore up a lot of your issues.
After this it comes down to situational stuff. If their team has a lot of magic damage and your jungler/top doesn't/can't get it for some reason, get it. If for some reason they have a lot of auto attackers, go for FH. Outside of situational team items, you can start focusing on just making yourself tanky. I prefer going for resistances (def/mr) over just flat HP(warmogs) because your hp taken from your W is based off your current HP, so the more HP you have the more you hurt yourself to heal. Also those items are expensive, which is why idc for them. Hope this helps.
Oh and you can try starting with
if you want, I did at first too, but I decided against it. It doesn't offer me sustain and raka isn't really a harass support, so I switched up for coin, but if you like it, go for it.