problem with loops and voids and saving outputs in a SD card

I am trying to save the values PWM (which active the servo)

What value in your program is that and how often do you want to save it ?
int inservo = 4 ; // entrada digital desde el servo a arduino/ input from servo to arduinoUnless you have a very special servo there is no output from a servo for the Arduino to read

an the same way i am trying to save the analog outputs from the potentiometer

I assume that this is the value that you want to save

    int outservo_val = analogRead(outservo);

But how often do you want to save it ?

It would be a good idea if you could explain exactly what you are trying to do and why.