The main problem is precise focusing at the particular area of interest. Your subject is a small part of your view finder view when you are using a non macro lens. Depth of field is very narrow at macro level so its necessary to focus exactly at your area on interest. It hard from a view finder without a view finder magnifier. But live view with magnification and manual focussing can be very helpful for the exact focus.
Here is the example for the technique.
Step 1, turn you camera to live mode and move the box to your area of interest on the screen. Keep in mind that lens sharpness is best in the central area so try to keep the box near the center and move the lens and camera itself for adjustment
Step 2, magnify and manually focus
Finally do the fine focusing at maximum magnification and take the picture. I didn't have the remote release so i had to switch my camera to delayed timer mode and take the pictures to avoid vibrations. Keep your lens's VR off with the tripod.
See the results below or click here
See the results below or click here