Movement speed is the #1 priority.
The biggest top tip for beginner PoE players is to focus on the big time savers, and not about extremely small time saves. For example, you should have a list of what to get in town, how much things cost, and when you can buy them. This will cause you to look for things while out in the world so that your next town trip can be better planned, thus reducing your time in town.
Learning how to read upper prison in Act I is cool, but it can take well over an hour to study a complicated layout like that. Reading layouts also, for the most part, disappears in PoE 2.0, being replaced by what I assume will most likely be layout Tells. One of the most popular layout-tells in the current campaign is that in the Western Forest in Act II, Weaver’s Chambers will always be on the opposite side of the road from the waypoint, and Alira’s Camp will always be on the same side of the road as the waypoint.
Watch someone gameplay in the format that you are trying to improve at. What I mean is that an act 5 world record is not realistic for a league start, since you wouldn’t skip over most skill points on a league start.
1-30 kill only blue packs and massive packs, skip all sidequests except quicksilver flask and never. stop. running. Kill shit when your quicksilver is on cooldown, run otherwise.
30-60 transition into a useful build and be more careful with your judgement to kill mobs. If your build is strong at this point feel free to kill any decent pack in 1-2 shots, if not just keep running and farm XP. Whenever you feel low in power go back and pick up passive points.
Always try to stay a couple levels under the zone level in 1-60. If you need to grind XP do it in the highest possible of one of the following zones: ledge, riverways, city of sarn, docks, dried lake.
60-75 farm dried lake, except on day 1 in a new league where you get stuck if you don’t immediately start building a map pool.
75-90 map anything, running your highest non-red map you can afford to roll.
90-95 try to build a high map pool and farm mad currency.
95-100 buy t12-14s constantly and run them non-stop. If you have a very fast clearing setup (e.g. bower + support) you will get similar XP in gorge, canyon (yes, a 75 map is competitive in xp with an 80 map even at level 99, just because you kill so much at once), arid lake and plateau. This stage costs a lot of currency and you will pull your hairs out if you ever end up dying.