The patterned ones come in a mixed box, as in a mixture of all patterns. You could have all patterns or throw in the plain one with slight marble effect (Hex Carrara Bianco) as in the attached photo from a Beaumont tile brochure. If your room is small you could consider the lighter version which is white and grey - Hex Blend Bianco.

Hi Sue, I think it would look amazing if you used some tiles with a bit of texture. The wood look tiles that are popular at the moment would be an example. If you chose a colour that toned in with your floor you would get a really nice cohesive look but with a bit of interest. I've attached a photo of a recent design of mine as an example. Just a suggestion!

also will give illusion of a bigger bathroom if you use bigger tiles ..I used small ones on one wall as feature wall and larger ones on other walls ..

I think she may have been referring to what is called a "French Pattern" which looks like a random mixture of square and rectangle tiles, often in travertine. However while it looks random it is actually carefully planned, and the tiles are made to a consistent thickness. It also depends on the type of tile that you are using. Many traditionally hand-made ceramic tiles have a natural variation, which adds to their appeal and visual interest. Other types of tiles, such as your porcelains are much squarer, flatter and almost identical. I would suggest that you go with your your choice of grid pattern, as laying a random pattern has too many risks (plus your tiler will hate you and charge lots extra). Be very careful about the selection of your tiles depending on your preference for a rustic more organic look, or a hard-edged architectural look. Make sure that the surface that you are tiling to has been properly prepared and is flat, smooth and true, as your tiler will not be able to correct imperfections if you have a bad wall. Best of luck, Dr Retro of Dr Retro House Calls