I think you may have a few typos in your instructions from the pattern, but let me take a gander at it. If I've misunderstood, please re-type the pattern instrux, being careful not to add typos to theirs.
"De[crease 8 st every fouthrnd, working one less st between decreases, 4 time more: 8 sts.
I have got 40 stitches"
Let's look at this one phrase at a time.
1)
Decrease 8 sts every fourth rnd.... You now have 40 sts. On the fourth rnd from now, you will evenly distribute 8 decreases (every 5th st), ending up with 32 sts.
2)
...Working one less st between decreases... Four rnds after that, you will dec 8 sts again, this time every 4th st. 24 sts in the round.
3)
...4 time more: 8 sts... Four rnds after number 2), you will dec 8 sts again, this time every 3rd st. 16 sts in the round.
4) Then, four rounds after that--and this is the
FOURTH TIME--dec 8 sts again, this time every other st. 8 sts in the round.
DCM