Nothing to really figure out.
- Farm rep / marks to buy vendor gear, allowing you to hit 31 (this already puts you WELL above the Vault of Glass raid because bungie screwed this up)
-- Marks reset every tuesday, can only get 100 a week
-- Rep/Marks is easy to farm with the weekly (now has matchmaking) and doing ROC strikes (assuming you have Dark Below DLC)
-- Stick with Vanguard, since the factions require Crucible marks
-- You need Ascendant Shards and Energy to max out the gear, you can farm these from public events, and doing the Daily. You can also get them from packages from the varying groups, or dismantling purple level gear. If you can do the nightfall, theres a chance to get a handful as well.
- When you think you're ready for a raid, try to find a group on LFG, or /r/fireteams or /r/DestinySherpa (people who carry first timers to help them experience and learn raids)