Analyze this game please! Give advice :)

Here's a game I would like people's thoughts on. In particular, what do you think were the weaknesses of the players playing?

White did not develop in the most logical manner IMO but black played with his eyes closed. Anyone can make blunders but to hang pieces in such a manner is just ridiculous.

So advice wise - black - look at the board before moving, white - think about how his pieces may be best placed to work in harmony.

4.exd5
Opening principal (don't initiate captures / move pieces twice / trade away center pawn)

5...Bb4
Middlegame strategy (preparing to trade "good" bishop when e4 and d5 squares don't matter)

6.Bg5
Beginner mistake (one move threat - forcing opponent to play a move they want to play anyway)

6...f6
Beginner mistake (moved f pawn)

7.Qe2+
Common beginner inaccuracy (countering instead of defending / blocking bishop / non-harmonious development)

7...Be6 
Beginner mistake (hang piece)

12.a3
Opening principal (moving pawns before development is finished)

13.b4 
Opening principal (moving pawns before development is finished)
Middlegame strategy (c4 hole, hook for a5 break)
Beginner mistake (forcing enemy piece to a better square)

14.g4
Opening principal (pawn moves before development is finished)
Middlegame strategy (hole on f4, no ideal shelter for king)
Beginner mistake (one move threat / losing material)

16...Rf7
Opening principals (non-development)
Beginner mistake (nonsense move)

17.Rad1
Middlegame strategy (rooks like open files)
Beginner mistake (playing for 1 move threats)

18...Na6
Beginner mistake (knight on the rim)

19...Rae8
Beginner mistake (hangs material)

21.Ne2
Beginner mistake (hangs material)

21...g5
Beginner mistake (hangs material)
Middlegame strategy (additional holes and light square weaknesses)

22.f5
Beginner mistake (hangs material)

Conclusion:
White should work on following opening principals, perhaps talk about moving pawns too much.
Black should work on seeing 1 move threats

     Holy crap!  Black is hanging pieces left and right.  Telestu is right, Black should work on seeing 1 move threats. 

Conclusion:

Study tactics, not opening principals. Like MDLM said in Rapid Chess Improvement "There is no opening that wins a piece by force. If you consistently find yourself dropping pieces in the opening, you have a tactical (not opening) weakness." Btw I may not be a good chess player, but I'm pretty sure his is right. Cheers! 

They both blundered a number of times but Sandex neglected development for quite a while. That's why beginners are always to to just following principles and develop. It's important to learn and it wins almost automatically against an opponent that doesn't do this.

Apart from Bg5 the opening is fine. White just transposed into a Winawer exchange which is fine.

The bishop is misplaced on b4, which makes exd sensible in the winawer exchange.

In this game, by altering the move order, it means both players made mistakes. The mistakes canceled each other out transposing into a line, but they still reveal thinking errors and/or gaps in knowledge.

Lol why is it that a beginner game I posted gets a ton of comments in a few minutes, while the game I played myself get very few comments/thoughts... 

Anyways, the black player said these comments were quite helpful, and he needs to slow down a bit, and practice a lot in terms of basic tactics and board vision simply - he didn't notice, for instance, that the bishop could be taken on e6.

And topics like "I want to be a GM, I think I can do it because I like horsies!" gets 100 comments a day, for 10 days straight, while Batgirl's thoughtful articles on chess history get a few replies total. After you read why though, the answer isn't surprising:

https://en.wikipedia.org/wiki/Law_of_triviality

I hope these comments aren't interpreted as harsh- it's just that the priority needs to be on making sure that these types of blunders stop. And the reason they happen is that it seems like black doesn't ask himself what the last white move did. That's a mental reflex that needs to be built. Priority.

That is your job according to your profile description...

as far as I can tell, his queen was pinned as soon as black moved queen onto the file in line with white's king, and white could not move queen off the E file at that point.

Thanks dpnorman - great analysis that the black player will see. 

*It's not a job of mine - "if I feel like it". 

*And yeah, probably a good idea, though I don't have a habit of checking which section I'm posting in...

To the tune of Folsom Prison Blues:

When I was just a baby,

My mama to me preached:

Always be a good boy,

Don't throw away a piece.

But I hung a knight at chess.com,

Just to watch him die.

When I see that analysis comin',

I hang my head and cry.

Looking up the game, I see it's a regular 30 min. game,  Yet, when it ended on move 23, White, the winner, had 25:04 left on the clock and Black had 21:11 left.

So you have two weak players who either don't know they need to spend more time looking over their positions or don't know what they should be looking for.

And it's obvious from their play that they are knee-jerk reacting only to the current position each move and not thinking beyond their answer to the current move.

For example, after move 12, Black has an undefended Bishop at a5 that's not doing much and might become an undefended victim of a fork or double-attack in the future.  He should be left out there on the edge.  So all 13 b5 did was make that B move to b6, where it's defended and attacking the White d4 pawn - White chased him right to the square he should want to be on!

When Black finally got around to developing his QN on move 18, he should have been looking at the potential N-outposts on c4 and e4.  The logical move progression should have been 18...Nd7 then to e5 then to c4.  Instead he plays 18...Na6?  With no place to move forward from there and no plan to push pawns to change things.

Black threw away pieces. White didn't see that 21 Ne2 meant he'd lose a N + B for a R - but Black didn't see it either.

It seems to me both players not only need a better understanding and recognition of tactics, they need a book that talks about a little strategy and what you should be thinking about between moves.  Dan Heisman's books are good places to start or his archives at ChessCafe.com.  His book  A Guide to Chess: the Best of Novice Nook has a long, 78 page chapter on the Thought Process alone. He talks about "Look wide, not deep," what happens when you take too little thinking time (games like this!), and what you should be thinking about.

It has chapters:

1. General Improvement

2. Thought Process

3. Time Management

4. Skills and Psychology

5. Tactics and Safety

6. Openings

7. Endgames and Technique

8. Strategy and Positional Play

9. Shorter, Lesson Material