Also rule of thumbs/tips for items and enchanting is the following (not including Monks because you have to look at secondary affix vs all res too):
*Past a certain point any Rare with 3 primary affixes (socket count as an affix so if it's 3 affixes plus a socket that's actually 4 affixes) is automatic dumpster tier. Salvage/vendor it with haste.
*4 affixes with 3 good affixes (like a glove with main stat/crit/ias) is automatic near top tier item especially for a Rare.
*For gems you want either Ruby or Emerald in weapons (Emerald if you have high crit chance for sure Ruby if you are doing like a Crusader heavy hitting nuke type build). Diamonds would be good too as +% bonus against Elites is nothing to scoff at but for now stick with Emerald/Ruby. Helm you want either Ruby or Amethyst. It's better to put in an Amethyst if you are new to maximize your HP. On armor pieces if you need more damage put in your main stat gem otherwise Diamonds for resistance. Don't bother with Jewelry that has socket unless the other 3 stats are trifecta.
*For Bracers you pretty just need 3 good affixes... +% element damage of your build, crit chance and main stat. Your 4th stat can be anything you want so you can make do with even 2 good Bracers stats. I would normally get All Res as my 4th stat or if you really need it then Life on Hit.
*For Boots you want main stat, movement speed for sure. If you are going for damage then you want a %damage roll for your skill. If going for tankiness get all res + vit. Simple stuff here.
*Pants you want 2 sockets, main stat and all res. If you want more damage then you want +%damage roll for your skill otherwise vit/life regen/armor is fine.
*Chest same as pants but your want 3 sockets here.
*Shoulders and Belts Main stat, all res, vit and a +% skill roll is solid. If you don't want skill roll then get armor/life regen. Pretty easy here.
*Jewelry is trickier. The 6 main offensive stats you need to look for are main stat, attack speed, crit chance, crit hit damage, + average damage and +% element damage. All of these are good but crit chance is really valuable so I would at least have that on all 3 jewelry. Get any 4 of these stats and you should be fine. Don't bother with defensive stats on jewelry, you need to make that up from armor pieces like shoulders, pants, boots and chest.
*Gloves is same as Jewelry, you want 4 offensive stats.
*Helm you want main stat, crit chance and socket for sure. 4th stat can be a defensive stat or a skill % bonus.
*Weapons need a socket and generally the highest DPS possible. So the affixes include +% damage, +% attack speed or main stat.
*Offhand items have a bit more complex requirements.
These are just standard gear recommendation that help out many builds. There are some builds that are much better with resource cost. Certainly a DH with 100% resource cost reduction can throw out twice as many Cluster Arrows which is a significant DPS boost despite not showing up on the sheet. Area damage is also a very powerful stat that is highly underrated. However these stats are harder to work into a build and you need to go into the game with a build in mind and work towards these specific stats. Not recommended for newcomers.