Tutorial how to make engine part 10

cylinders
Step 1:
open a sketch on right plane and draw a axis for new plane
Step 2:
create a plane that have to be 35 degree between new plane and right plane. then open a sketch and draw 4 circles
Step 3:
draw two circles like shown
Step 4:
use mirror command two times
Step 5:
finally make your sketch like this
Step 6:
use extrude commad
Step 7:
open a sketc under the body and draw two circles. smaller circles radius is 50mm. other one have to be bigger then body. then use cut extrude command and enter volues
Step 8:
open a sketch on cutted surface and draw circles like this
Step 9:
make your sketch like this
Step 10:
use extrude command
Step 11:
use linear pattern command. you must to decide that how many cylinder you want. I prefered to make 12 cylinder.
Step 12:
now we will cut the surplus portions. please check the photo and try to draw a sketch on the body like this. you should use linear pattern command
Step 13:
use the command and cut the body 70mm. That's all for now. please follow the tutorial step by step. if you have a problem with the tutorials please let me know
Please Provide the Dimension For Extrude.
please make last step more explanatory
What's radius on step 9? I haven't figured it out and I'm getting different results on part 11.
Step 2 is vague. Please reword.
please reword step 2 it really not clear