The key thing to understand is that the new skill system overhauls everything about how abilities work. Your character starts with 9 dedicated slots that handle all your active skills instead of messing with gear sockets, which is way cleaner for planning builds. Each skill starts with 2 support sockets but you can push that up to 5 using jeweler's orbs, similar to old 6-links but more reliable.

When you're setting up skills, you'll be working with uncut gems that let you pick class-aligned options at different power tiers, and here's something interesting - support gems can only be used once per build now which really changes how you stack damage. The timing on using these support gems matters since attribute requirements from the passive tree directly control how many of each color you can slot in. Like if you grab 10 strength nodes that gives you 2 red support slots to work with.

Watch for weapon requirements when picking skills, especially as a mercenary since crossbow abilities need specific gear. The new meta system adds some cool layers - persistent buffs will eat up your spirit resource to maintain stuff like auras, while meta gems activate other skills when specific conditions trigger like building up enough energy to drop totems. Really important to note that any class can technically use any skill gem though, so don't feel too locked into specific builds just focus on meeting those attribute requirements through smart passive tree routing when you're planning things out.

Line this all up right and you've got way more build control without the old socket rng headaches, just make sure you're thinking about support gem limitations since you can't stack multiples anymore.