So basics first - get my materials sorted.
Brushes - no problem. My wife had bought me my first set - Windsor and Newton Gold Sceptre which comprised a No 8 round, No 2 round (?), 3/4" chisel and a rigger. This has been my basic set up ever since and though I have added a few more over the years I still rely on these battered but good old friends - I know exactly what they can do and reach for the right one for the job automatically. I do get a bit of ribbing from colleagues when I put out these seasoned old veterans - but they work for me and if it ain't broke - why fix it!. The largest brush I have is a 1" chisel brush and I once painted a 5 foot x 3'6" foot watercolour with my trusty set, so I have never bothered with anything larger!
Too many! How can you ever get to know let alone use the combinations in such a number. So when I am asked what do get if you mix quadrionix blue with vertiginous green - I give my stock answer - "Try them, it will be interesting to see how they mix together." I could of course just reply "Muddy Grey" and would be right 99% of the time!
I gradually fixed my palette at just eight colours, two of which are classed as 'emergency' colours which thankfully I use less and less these days, but they are always there ...just in case. I began with and have remained with Windsor & Newton Artists Watercolour paints. I know exactly how they react with the paper and each other so have totally resisted all blandishments to try something different.
Finally paper. It took me three years before I found somebody to explain the different weights and surfaces of paper. In some respects, the paper you choose is probably the most important decision you make to achieve an 'infallible' technique. I need a robust paper that can take a lot of water - and I do mean a lot of water - will let me use several layers, cope with masking fluid and even let me 'scratch out' if necessary. Eventually I settled on Saunders Waterford CP 140lbs because in addition to the qualities above it has a beautiful look to it.
With these basics sorted out I could then concentrate on the subject I wanted to paint. I haven't yet discovered an 'infallible' technique of course... I'm not even sure that I would like to! Anyway with watercolour there will always be the element of chance where the paint and water will do its own thing no matter how experienced you are. That and the fluidity is what gives this marvellous medium the edge over all the others.
Finally after much study I have come to the conclusion that ultramarine blue is best for our English skies. It is slightly warmer than the cobalt (and a good deal cheaper - not that this would ever influence a Yorkshireman like me!), so is the one I always use.