We should start posting screenies of nerds raging cus they got backdoored. Those bushes are cheap backdooring is not. It's an exploit yes, of the enemy's stupidity.

As soon as u have bought an item, it's equiped, and does whatever it's supposed to do.
Unless it's a consuamble item (potion or ward) then u have to click the item in your inventory.

And to answer all the item buying questions:
When you buy a build, where u need other items before you can get it you can just click on the main build, the item you want and then, if u have enough gold you can buy it right away. This enables buying combo-items even if you have 5 or even 6 items already as long as one of the six is a part of the combo item.
About the price for the combo item. It's the same if you build it one step at a time or if you get it al at once. If you click the main item before and after buying a thing needed for the build you'll see that the price has gone down the with the same amount as the item you just bought costed.
The price listed when you click on it in the left part of the shopwidow is the price for the "recipe" itself. The price you get if you click on it in the right part of the shopwindow is the price you need to pay to get it (it has substracted the cost of any needed items).
Hope this doesn't make it sound too complicated, 'cause it's rly pretty simple, when u realise how it works.

hey ppl, i'm new to the game and i mostly know how to do everything, but what bothers me is that i get killed way too many times. Can you give me some tips? I'm using Ryze the mage. Thx a lot

Are there hotkeys for using inventory items? or is clicking them the only way?
Potions/items with activate powers.

1-6 keys, I do believe. I've never actually bothered myself, but that's what I've been told.

Thanks so much. I was looking for that bit of info haha