[1] The original 1600x1200 picture, snapped with a digital camera. Oops, sorry about the shoes.

[2] Copy and paste to transfer the image to a object/layer. Switch the layer to rotate/skew mode and rotate slightly to sraighten out the horizontal lines.

[3] Line up to the centre  line/s using the upper/lower window frame.

[4] Switch to perspective mode and pinch the left hand side, slightly, to further straighten and correct any horizontal perspective distortion. You should now have nice parallel horizontal lines.

[5] Now for the vertical lines. In rotate/skew mode again, skew the top central 'handle' to the right to straighten the vertical. Use the side window frame to check the centre lines.

[6] As before, correct any vertical perspective distortion by pinching the bottom of the image. To finish this stage double click the object/layer to apply all these transformations.

[7] The next step is to trim the image down, taking away all the wonky edges. Then offset 50/50 to check the tone and colour balance. As this picture shows the top to bottom is OK, but the right to left is a bit off - too  much red on the right, and too much green to the left. Undo the offset and make corrections using a graduated mask and the hue correction dialogue box. It needed a bit of lightening on the right as well.

[8] With the tonal and colour corrected, we can tile it from side to side by offsetting at 50/0. I lucked out here -as all except one  of the horizontal lines matched up!

[9] To correct this use the mask brush to mask out the wayward line, copy and paste, then rotate and/or move to match up the line. Touch in any visable defects with the clone brush.

[10] Next trim the top and bottom edges so they will match each other - just below a horizontal line at the top and just below the line at the bottom.

[11] Now the top and  bottom edges can be tiled, by offsetting at 0/50. At this stage  adjust any upright lines that don't look right, like these, which don't stagger naturally with the bricks above. So copy, paste a new object /layer from a retangular masked area and move to the left before merging with main image.

[12] The only thing remaining is to continue the brick join lines and blend the brick edges along that central join line using the clone brush and smudge tool.

The finished tile. Full size versions of this are available in the free texture section.

[13] Should you not be so lucky as I was here and the bricks totally mis-match, which would be quite likely on something like a more random stone wall after stage [8] a selection from one end or the other can be copied and pasted as an object (layer), as shown.

[14] This can be then be moved across little by little until a better match can be found. Remember that smaller edge areas can be selected and cut from the object/layer if you spot a match underneath. When happy, trim the whole image to the edge of the object/layer, whether to the left or right, then merge with the main image. As before, the clone brush and smudge tool can be then used to blend it all in. If necessary this process can be repeated on the horizontal plane after offsetting the top and bottom edges 0/50.