First of all - don't "feel the planes" - you should really see the planes and dissect sharply under direct vision. Get used to every approach as each has it's place and when you have trouble it's good to have a backup plan. eg - in the R. colon you can go 1. lateral to medial (most common approach during straightforward open cases), 2. medial to lateral (seen more often in laparoscopic but useful for a locally advanced tumour with invasion laterally or posterior) 3. inferior (my personal favorite approach) - you lift up the cecum and TI and enter the plane posteriorly and extend it up until the duodenum is identified) and finally 4. superiorly you can start at the flexure, get the flexure mobilized and up off the duodenum and work down.
The best advice is good traction and counter traction. If the tissue isn't under traction then you won't see the plane. It's really the assistant that does the case and not the one doing the cutting (but don't tell my residents that because they think they're doing the case - hehehe).
