Activity.
Main idea?

"Donut"
In more than one word, at my patzer level OTB it is usually more like:
1) tactical check on both sides:
- any check moves? (and consequencies)
- any attacked piece? (and consequencies)
- anything to threaten?
2) strategical planning:
- identify imbalances, and weaknesses (isolated pawn, double pawns, weak square, bad/good piece, lack of space, etc)
- is there any possible action to take advantage of the existing weakness or to create them?
For instance:
* isolated pawn: control of the square in front of the pawn to prevent it from moving forward and being exchanged, more pieces pointing at it to force my opponent to defend the pawn, control of the adjacent file and manoeuvers around it once my opponent put most of its pieces to its defense.
* affected by a lack of space: try to trade pieces
* opponent affected by lack of space: avoid to trade pieces
etc etc

Ok. Hard to follow all.
Did you mention that if you are leading in material it is often benefitical to exchange pieces with same value? Let say you are leading 10/9. Then 9/8 is relatively bigger than 10/9 and 8/7 > 9/8 and so on .... 2/1 > 3/2...You get that math?

Yes, it's not exactly a discovery.
I cannot do it simplier, there are only a tactical and a strategical aspect with no more than 3 general ideas for each one.
If you don't get it, forget for a second the examples after "for instance", it's just basic knowledge about strategy (but you should definitely learn about it later).

Yes, yes. "Tactical" and "strategical". But those are just words. And maybe they are hard to translate to finnish. What is different between tactical ideas and strategical ideas? They are just ideas how to play chess. Why two separate aspect?

Tactics are what you do when there is something specific to do. A strategy is something that you consider at all times. The strategy is the plan and the tactics are the specific details used to implement the plan.
For example, in terms of chess. You may have a strategy to create a certain weakness in your opponent's camp, but you need some specific moves/trades/captures or tactics to actually achieve your goal.
The strategy is the idea. The tactic is the way that it was achieved.

If you don't see the difference, it would not be a bad idea to buy a book on chess strategy.
Really, no irony.
I do my usual groupie's advertisement:
Winning strategy by Yasser Seirawan

ok. I buy it if somebody translate first in finnish :) My english was 5/10 at school. I have search some finnish books, but I havent found any. And other problem is that it is hard for me to follow a1, a2,...,h1,...,h8 marks. I have to see the pic.
EDIT: Correction: I ordered the book from Amazon! :) Hope I learn english at the same time.

Depending on the position(and my skill level) these are a few of my main Ideas after or as I make a move:
anxeity safety embaressment trepidation Hope

Depending on the position(and my skill level) these are a few of my main Ideas after or as I make a move:
anxeity safety embaressment trepidation Hope
Agreed! Also thoughts like, "maybe?"; "We'll see what happens"; "Ugh! I have no idea what I'm doing"
What is your main idea when you move the piece if you have to describe it in one word? I would like to know, because I just sometimes move pieces without any good reason: I just threaten for example Queen, but it gives to the opponent the possibility to put his Queen to the better place. I just move because I have to because clock runs. Ok, if it to put pieces to better places, how it is defined those better places?