Some tips for beginners who are struggling.
Level up whatever you think your player is struggling with, so if its ki regen, level up courage. And level up with whatever your favourite wepon is. Level up your character to suit your playstyle.
If your player is taking a beating and you have better equipment to equip but it makes you move to slow then level up your stamina, I tend to stay just below to 70% encumbrance so I can still move a decent speed, keep it in the green.
Summon the ai to take the aggro from yourself and use them as cannon fodder as most are useless. Attack the back whilst they attack the front. You can break down items for ochoko cups at the shrine or kill revnants.
Learn to ki pulse (R1) and at least learn all the running water skills in samurai, earth, man, heaven so when you dodge you ki pulse, dodge backwards at the end of your combo. I find this much easier to remember.
Get sloth as soon as you can and level up magic a bit, it slows down enemies and its great to use on bosses and harder mobs along with your guardian spirit (triangle, circle) always make sure that's full before a new boss fight.
Bosses tend to have an elemental weakness so add that to your blades, some weakness are very obvious. Can do some serious damage.
Try and get as many kodamas as you can whilst going through the levels, check your items for a kodama sensor and equip it if possible as these will put little green circles on your compass thing in top left of screen showing you there location. Or use guide. Then equip the healing blessing so you've always got a nice supply of elixers. Replay easier levels if your running low.
Change your stance based on enemy type, I use high stance for when I'm in tight spaces especially bridges you can fall from, mid stance most the time, and low stance for speedy enemies like the medusa snakes on 3rd story mission.
I use dual blades so windstorm is a must, can wipe out revnants easy just spamming this move just like the last game.
Kill revnants for the items they carry, especially ones higher level then yourself. This is how I get most my top gear. Same as last game.
Use your gun or bow before enemies notice you for some serious damage, can kill alot of things in one head shot and is great for taking out groups of enemies before they even notice your there. So stock up on arrows and bullets when you see a shrine.
Use R2 and circle whenever the bad guys turn red, if they hit you it's gonna hurt. Learn to time it right and you'll counter and do some serious damage to them.
If your having trouble with an enemie in the dark zone, try and get him to follow you to where it begins, back to the normal world, so your ki recharges quicker and lay into him, it'll respawn eventually with all the health you took off missing and give you a breather. Rinse and repeat.
And when you've done with a level, become a visitor and help another player out as much as possible. You can gain amrita without the worry of losing it when you die. And your helping a fellow gamer out in the process, win, win.