Draw a six-membered ring as a zigzag hexagon
Place one carbon at the left front and one at the right front
Draw the two front carbons slightly lower than the two back carbons
Connect the carbons with alternating up and down bonds to form a chair shape
Make one side of the ring look like a raised armrest and the opposite side look like a lowered seat
Keep all bond angles approximately tetrahedral
Add substituents in axial or equatorial positions as needed
Draw axial bonds vertically up or down from each carbon
Draw equatorial bonds outward and slightly slanted from each carbon
Check that adjacent axial positions alternate up and down
Check that adjacent equatorial positions alternate opposite directions
For the flipped chair, reverse all axial and equatorial positions
Redraw the same ring with the opposite carbons raised and lowered
Keep the connectivity the same during the flip
Place substituents in the corresponding flipped positions
Verify that the chair is not flat and does not contain planar angles