General tips

https://sites.google.com/site/trumpdecks/frequently-asked-questions

-Count card value as how much cards you had to use to handle how many cards
If you have to use Kok'ron Elite and Execute to kill a minion, that's 2 for 1, therefore bad

-There's two types of play,
Control, where you always control the board and slowly build up your board.
Aggresive where you go face and force the enemy to run their monsters onto your monsters for them to avoid damage.

-While you may be tempted to pick the value cards rather than the situational ones, if you already have stable 2-3 turn plays, you should pick Dark Iron Dwarf over Senjin since you can kill 4 health minions, whereas Senjin is more to stabilizing the board and slowing down the enemy. Why try to stop enemies when they're not really ahead?

-Tempo: Hearthstone is a tug of war game and tempo is the pace of that game - at any point one player is 'tugging harder' and has the rope on his side - in other words, has board advantage. Tempo is getting an advantage from how well you use your mana relative to your opponent. A good example is a card like Backstab, which doesn't do much as a card but also lets you use your mana for something else. An extreme example is using a card like Sap, which spends your two mana to temporarily remove an opponent's minion which could cost significantly more than two mana.

-Value: Value is the vague concept of "getting more for a card and/or play than you usually would." A basic example is "My swipe killed three guys, that's value!" or "My Cult Master has drawn three cards over the course of the game, value!"