I tend to work from the floor upwards (well, the floor is rather important!). Floor choices include natural stone (hardwearing, attractive and reasonably easy to maintain and clean, but a bit more likely to stain than ceramic tiles, and one of the more expensive options), ceramic tiles, which don’t have quite the same character as natural stone but are pretty much bulletproof and are generally cheaper, and terracotta (very distinctive, which can sometimes become a problem, plus they can chip quite easily).
Then there’s wood flooring, which is obviously not as hardwearing as stone and ceramics, but is perhaps nicer to stand on (would not recommend for a farmhouse kitchen with resident Labradors, sheep etc though!). Engineered wood flooring is a better choice for underfloor heating or damp areas, but it tends to be more uniform than solid wood. Lino, which is essentially a natural material, has made quite a comeback and is available in a huge range of patterns and colours, and is of course easy to clean and pleasant underfoot. Vinyl tiles offer another choice, as does natural rubber.
Whatever you use I suggest that the same floor finish is used throughout the kitchen and any adjacent dining or living areas, perhaps using rugs to soften these spaces, rather than using a combination of finishes.
With the advent of washable modern paints its no longer necessary to use wall tiles, which I personally am not very fond of as they can give the kitchen an institutional feel, and once installed its not easy to alter the décor in the future. They are of course a good choice behind cookers and hobs, although other alternatives for these areas include backpainted glass (easy to clean and unobtrusive if painted the same colour as the wall), stainless steel (practical but not so easy to clean), and patinated zinc.
When choosing floor and wall finishes its obviously important to consider the kitchen furniture and surfaces. For instance I wouldn’t recommend combining an oak kitchen with natural oak flooring as the overall effect would become too, well woody! Some contrast between horizontal and vertical floor and surface finishes adds texture and contributes to a feeling of space.