Tactics don't prevent blunders...

I keep reading that I shouldn't study opening and tactics are most important, but most games I play I blunder within 6 moves. I analyze after the fact, but during games I just don't trust myself to make the right move. Should I break down and memorize 5-6 opening moves in a standard opening and defense to avoid these early blunders? 

An example game:

https://www.chess.com/analysis/game/live/19414060241

The main problem is that Slibbidy calculates exactly 0 moves ahead. By that I mean that he makes random good-looking moves without even considering if the opponent can take any piece in the very next move.

The good news is that it is easy to improve from that. No need to learn anything, just pay attention to the game. At least a bit of attention.

Youre a beginner playing speed chess.  What were you expecting to happen?

If you cannot go through each of these spreadsheet without losing on time?  Youre moving to fast.

Opening Principles:

1. Control the center squares – d4-e4-d5-e5
2. Develop your minor pieces toward the center – piece activity is the key
3. Castle
4. Connect your rooks

Tactics...tactics...tactics...

The objective of development is about improving the value of your pieces by increasing the importance of their roles. Well-developed pieces have more fire-power than undeveloped pieces and they do more in helping you gain control.

Now we will look at 5 practical things you can do to help you achieve your development objective.

They are:

1. Give priority to your least active pieces.

• Which piece needs to be developed (which piece is the least active)
• Where should it go (where can its role be maximized)

2. Exchange your least active pieces for your opponent’s active pieces.
3. Restrict the development of your opponent’s pieces.
4. Neutralize your opponent’s best piece.
5. Secure strong squares for your pieces.

Don’t help your opponent develop.

There are 2 common mistakes whereby you will simply be helping your opponent to develop:

1. Making a weak threat that can easily be blocked
2. Making an exchange that helps your opponent to develop a piece

Pre Move Checklist:

1. Make sure all your pieces are safe.
2. Look for forcing moves: Checks, captures, threats. You want to look at ALL forcing moves (even the bad ones) as this will force you look at, and see the entire board.
3. If there are no forcing moves, you then want to remove any of your opponent’s pieces from your side of the board.
4. If your opponent doesn’t have any of his pieces on your side of the board, then you want to improve the position of your least active piece.
5. After each move by your opponent, ask yourself: "What is my opponent trying to do?"

Bingo, and while I'm playing I have absolutely no idea what I'm trying to accomplish. How do I learn to calculate what's a good move vs a dumb one? Tactics have helped but I can't get into those positions in the first place. There are times when I'm analyzing and the best move is to block a column with a knight and it's a move that would never occur to me because I'm just putting the knight at risk. I need to figure out how to change my thinking, and tactics doesn't seem to be doing it, even if I am only a 1650 or so on them.

IMBacon, I promise I'm trying to do that checklist, and I realize I'm supposed to be terrible. I just started. Take #2:

2. Exchange your least active pieces for your opponent’s active pieces.

What constitutes an active piece? Just in the middle? threatening another piece? What is the algorithm I should be using to determine where I am on that checklist?

An active piece controls a lot of squares, where an inactive piece doesn't.  A very basic example of what im talking about.

Count how many squares blacks DSB controls vs. whites undeveloped DSB.

Looking at that position, how would I accomplish attacking that piece? b and d pawns are just lost immediately if I move either to 4. Would ne5 be a proper response? Should I try to defend f3 with my queen? Maybe bd3 or bc4?

I'd probably choose ne5, but then am I hanging my knight? This is just 3 moves in and I'm already unsure of what to do. 

That was just a basic example comparing an active and an inactive piece.  You obviously cant exchange those bishops right now.  As far as what to do in that position? 

Its whites 4th move.  Go over those cheat sheet i posted and figure out a move.

White to move.

In my opinion - tactics DO prevent blunders. But how? Just ask yourself what would you do if you were your opponent. If you see good move for them such as powerful pin, fork, skewer or removing the defender make a move that prevents them from doing that. Most of us ignore our opponents plans but we cant forget that he or she is also playing to win. Most blunders are made because of not seeing a great tactical combination of moves for your opponent that becomes possible only after you make your move. After all there is a saying that chess is 99% tactics.

Looks like ne5 was the best choice, and then retreating if they push d6. I guess the "never move a piece twice before the other pieces are developed" doesn't apply when a piece is threatened.

In the game you played 4.Bc4.  So did you learn something, guess, or?

"After all there is a saying that chess is 99% tactics. "

A quote that is not entirely accurate and is argued about all the time here.  The rest of that quote should be:  "Tactics flow from a superior position."  So how do you get a superior position?  By knowing strategy. 

Piece activity.

Space.

Pawn structure.

Lead in development.

King safety.

Weakness in the opponents position.