1. Jeans are great. But wearing them every day is boring. Most importantly, you will never let out the stylish man that lies within if you always wear jeans. Get some variety.

The jeans that you do wear should be a raw denim, starting indigo dark and relaxing into true blue as you wear them, imprinting your own creases and folds. They are like good shoes, and indeed most good clothes. They improve as they are worn and become more personal.

2. The waist can be altered. When you try on a pair of trousers, it is instinctive to buy the pair that fits on the waist. But it’s easier to alter the waist than the drop, thigh line or anything else. So make sure the trousers are right everywhere else, and then get the waist altered if you have to. This includes jeans – I don’t care what the denim heads say about the chain stitch. Don’t get raw denim altered until after it’s been worn and washed, though.

3. The other pair of trousers you want is grey flannels (pictured top). Suit trousers, by which you mean worsted wool, are too smart to work casually. They are smooth and sharp for a reason. Chinos, or khakis, are a straight alternative to jeans: just as casual, workmanlike and performing the same role in a off-duty wardrobe.

When you want something smarter than your old jeans, go for grey flannels. They can be cut slim, with turn-ups, a low waist, flat front and a flapped rear pocket. In that guise they go with fitted T-shirts as well as Oxford button-downs. They go with any knitwear you own. Go out and buy a pair, or have some made.

4. Trousers take a lot less time and skill to make than a jacket. Yet they will often be a third of the price from a bespoke tailor. So buy them off the peg and get them altered (waist, length, narrowing leg), have them made to measure, or go to a cheaper tailor.

5. A beginner’s wardrobe should contain: indigo jeans, grey flannels, cream chinos and brown moleskins. Then branch out into white cotton trousers (not jeans), khakis in earthy colours, and corduroy (to avoid associations with your grandfather, see fit details in point three).

Only at that point should you flirt with linen, gabardine and bright colours. The latter, in particular, require a mastery of accessories and buckets of attitude to pull off. You may well have developed those two during the previous, seven-stage trouser journey.