if you need to kill something fast, a dual wield power attack in their face should do the trick, or at least cause some serious damage. also, a double normal attack is good for finishing off a weakened opponent (with style, i might add)

Cast Healing and Equilibrium at the same time to drastically increase your Restoration skill. You will never run out of magicka or health!

Conjuration

Re-casting bound weapons while near enemies will instantly level your conjuration, this will slow down at around 40 (will take multiple castings)
Conjure familiar is largely useless and is only good for the first 5 or so levels, get a atronach asap
Using a bound weapon + summon will increase conjuration really quickly, and it still raises your skill level so that you can switch to normal weapons later.


Smithing

Is too powerful, try and not use the skill but rather collect your gear out in the world. You will get much more suprised and achieve a greater sense of accomplishment when you pick up a really nice item in chest or body
Use lockpicks 'treasure hunter' perk to help pick up good gear rather than smithing.

Fast traveling while encumbered

When encumbered you can get on your horse and fast travel.

if you are a mage and are out of magicka, remember to use a shout while it is recharging

if you are stuck in a dungeon and dont know how to advance, equipping a torch can show a hard to see lever or passageway

get into the habit of saving often (eg every 6 or 7 minutes) and have multiple save files (atleast 5)

whilst in dungeons, pick up light high value items such as potions and garnets but dont bother with heavy low value items such as ancient nord swords

read up on the daedra quests before you start them if you really want that Oblivion Walker trophy. Its easy to miss due to not getting the artifact. Particularly the Masque of Clavicus Vile and the Staff of Corruption

Incorrect. Using ANY shout in town may spawn a courier to help you with that.

Buy the spell book: muffle. Use it every where you go.

Not incorrect.

I simply changed it to Relentless Force to not have folks killing innocents to get a map update.
Although i shoulda' mentioned that it's probably best to find a place with nobody around to pull this off.

Forsworn briahearts are tough enemies to deal with, especially at higher difficulty level. However, there's a way you can instantly kill them without any troubles.
If your sneak skill is high, you can go in sneak mode and steal their briahearts and they will die.

- The by far best selling enchant is Banish. If you plan on making money learn it, use petty gems (make sure they will result in at least one charge) and sell iron daggers.
- If you obtain the "Fiery Souls" enchant: The Fire Damage will not be reduced when adjusting the slider to the left but the charges increase.
- Followers can fill soul gems for you.
- Become Ethereal (Shout) can be used to negate falling damage or trigger traps safely
- Followers will use health and mana potions if given to them
- Most Followers do not level with you (only the dark brotherhood assassin does).
- Even if you plan on using light armor: Go the heavy armor path since Dragonscale can be reached from both sides but heavy armor contains better weapons (daedric)
- If you plan on leveling Enchanting or Alchemy: The Winterhold College plus Archmages Chamber contain a high amount of ingredients and Soul Gems that will automatically restock and are not considered stealing

Could post a lot of power leveling Tips for most skills here but I think most of this tips are already known or can easily be found on the wiki pages.

unrelenting force

Learn to use everything from shouts to potions to random scrolls to your advantage, its easy to rely on just unrelenting force and a sword when you have something that can make your life easier

But the tip was still incorrect. You said it like a flat fact, that one can only use "Unrelenting Force" (Relentless? Do you have it on another language and are translating it differently?) and get the courier.

And that's simply not true.

Never sell or waste the fish called "River Betty." Poisons made from this fish do huge damage (I think more than 2x normal) and can also slow.

For players who go through the main quest, this is not an issue once you can start farming Crimson Nirnroots since these plants yield even more powerful poisons.

Might be a bug, but the fear illusion perk adds 10 fire damage to fire spells, making the flames spell much more useful, doing 20 damage per second for 6 magicka per second at early perk levels.

The sneak roll is very very helpful when combined with the quiet running perk. When you start to get detected you can usually roll away fast enough to avoid them finding you.

The block perks are silly helpful (other than the +5% effectiveness block perks, which are silly wasteful...)

If you need to train archery, horkers are great practice targets. They move too slow to ever be a real threat, and at low levels they can soak up a lot of arrows.

-Steed stone(just west of solitude) counters any penalties from wearing heavy armor and grants 100 extra carry weight, it's immensely helpful early game.
-You can power bash/disarm with a 2h weapon
-Letter's from a friend will guide you to word walls
-You only need 1 stamina to power attack/bash: use a veggie soup to give you stamina every second!
-Making Iron daggers then using petty/lesser soul gems to enchant them with banish will not only make you tons of money but level up smithing and enchanting quickly!
-Become ethereal makes you invulnerable; useful for absorbing a dragon breath or jumping off a cliff and has a short cooldown when using only the first level. You can cancel it at any time by performing a hostile action.