Hi,
You can reference my Ritualist pets starter guide from last year. I haven’t updated it in a while because I’m lazy, but it’s barely changed with the latest patch.
Mine is aether based conversion from Warden’s Judgment weapon, but all the other gear can transfer to a starter vitality setup. If you plan on sticking with the vitality route, you might want to reference one of the pet guides on the forum that’s based on the Lost Souls set or maybe Guardian of Death’s Gates. That would give you some ideas on eventual gear, skills and devotions to shoot for. I’m not that experienced with vita pets myself.