We do not recommend you do this, and any sails that are installed this way will invalidate the 1-year guarantee if the sail becomes damaged.
The eyelets are fixed directly into the material of the seam of the sail. The placements are in each corner and at regular intervals of 30-40cm (depending on the shade sail size) along each side for suitable installation support. If you do not use all the eyelets, additional pressure will be added to the ones which have been used and may cause the material to tear.
For corner installations only, you would need a sail with concave edges and D rings. The D rings are attached to the sail by thick webbing, which is sewn into the shade sail seams, and allows for the sail to be pulled in each corner and tensioned. The concave edges are not as deep as our ready-made shade sails, and you can see some examples of this in the pictures on our Customer Gallery - DIY Made to Measure Shade Sails page.