Cleaning up drawings

I like to know how I can clean up my design drawings. I usually print the 2D technical drawing to review dimensions etc and make sure all measuements are correct. At the same time I can see where something is not right. For example on my latest design I have a plastic tank bottom with 2 inch diameter holes but when I print the 2D drawing the holes don’t come up with a clean 2” diameter circle but instead has other points along the circle. I created the hole using a simple extrusion from a sketch. Is that the best way to do this? Any suggestions. Are there any tutorials on how to clean up your sketches prior to printing or sending them as DXF files etc. Thank you