I suggest taking the time to read the tips during the first part of the game.
Depending on your gaming preferences and challenge expectations: Keep in mind that arguably rogue is the most "challenging" class, daggers more so than archer (and potentially more fun, for some people), followed by warrior (2H then tank) and lastly mage.
Also be ware that whichever difficulty level you chose, the first part of the game will be a bit more difficult, gradually becoming easier as you make progress, so don't be discouraged if you find yourself on a tough spot early on as you gain more abilities and gear up. Crafting is a good way to improve your character (there's no level requirements for crafted gear) but know that if you make a point of crafting higher tier gear you may end up trivializing the difficulty.
Feel free to switch around between controlling each of your party members, it will give you an idea of the different classes.
Other than that, follow standard RPG strategies, have your tank take the bulk of damage, burst squishy enemies first, and happy killing.
Feel free to ask any specific questions that may come up as you start playing.