Hi Faruk, welcome to the list.

Create a counter that will count up or down between 0 and 7.

For the stepping up you can call the following subroutine:
STEPOUT     INCF        COUNT,W ;or DECF for other direction
            ANDLW       0X07
            MOVWF       COUNT
            CALL        STEP
            MOVWF       PORTB   ;pins RB0 to RB3 are the stepper pins

;ADD YOUR OWN DELAY HERE TO CONTROL SPEED, MINIMUM IS ABOUT 10Ms
(FASTEST STEP)

            RETLW       0       ;and go back see if button is still pressed,
                                ;if so, call STEPOUT again

;select one of the STEP routines below according to your needs (use only
one!)

;HALFSTEP, SLOWER, MORE POWER
STEP        ADDWF       PCL,F
            RETLW       B'00000001'
            RETLW       B'00000011'
            RETLW       B'00000010'
            RETLW       B'00000110'
            RETLW       B'00000100'
            RETLW       B'00001100'
            RETLW       B'00001000'
            RETLW       B'00001001'

;FULLSTEP, FASTER, LESS POWER
STEP        ADDWF       PCL,F
            RETLW       B'00000001'
            RETLW       B'00000010'
            RETLW       B'00000100'
            RETLW       B'00001000'
            RETLW       B'00000001'
            RETLW       B'00000010'
            RETLW       B'00000100'
            RETLW       B'00001000'

Nice to share something that I've learned from this list a long time ago
and still use. :)

Quentin