If you are a new player of Path Of Exile, you will more or less encounter some problems in the game, but you don't need to worry, these should be encountered by many novices. We have also collected some problems and provided the corresponding answers. I hope this will help you.
I have a single gem socket available in my templar guardian's gear. Which is the best gem to use for buffing sentinel of purity damage?
Dread Banner will probably want to be linked to Generosity support as your Impale scaling is limited by available impale chance (Dread Banner+aura effect, Impale support, and Cluster jewels) if you go that route.
Flesh Offering is good but you will need to Desecrate to have corpses available against a single target.
Carrion golem's flat base damage doesn't add much to Sentinel's already large base damage.
Vulnerability is probably your best bet here although bosses have some curse effect resistance. For a balance of clear speed, defense, and some damage the reworked Punishment curse is also a good option.
Will smaller ignites override a larger ignite?
no. you can have multiple ignites present on the enemy that will run their duration but only the highest DPS one will actually deal damage.
What skills work best with the cast on crit other than ice nova?
Discharge requires the threshold jewel. Ice Nova only works because it casts on 2 Frostbolts for double the effective damage, and you can easily trigger Frostbolt with Cospri's Malice. You could make it work with a bow using Asenath's Chant. Bow versions can also use other projectile spells that scale together with the supports for the main attack skill.
How strong is the lightning golem aura?
You can find it in Path of Building. Just add Lightning Golem to your skills, and turn on Lightning Golem's Wrath aura in the Configuration, and check the added minimum and maximum lightning damage for your skill.
If you encounter powerful enemies in the game, don't forget to take advantage of POE Currency. Only by making yourself stronger can you deal with harder enemies in subsequent games.
If you don't have enough time and patience to grind POE Currency in the game, you can come to PoeCurrency.com to buy whatever you need, Exalted Orb, Chaos Orb, and Orb of Fusing, etc. And their prices will be so cheap that you will be shocked.