The important factor here is to first decide, do you really just have a fixed mind on a style that you really want to own and wear and therefore nothing else really matters. If this is you, then just buy what you want and enjoy it. You can also get another jacket later on if you decide you want a change. If on the other hand you do not have a fixed style in mind and what to buy yourself a jacket that you can wear and be admired in the here are the basics:
Tall Men & Women
If you are a woman that is 5'10" or over then you will need to opt for a classic or designer style biker in a longer length as the traditional style cross over zip jackets are likely to be too short in the body for you. We would suggest that you measure the centre back length of a jacket that you have that is the right length on you, usually this would be at the top of your hip bone, i.e. just above it. For men over 6'2" who are long in the body the same would apply.
Rounded Apple Shapes
For those that do have a tummy then the traditional biker jacket that sits at the waist and broadens out through the chest to the shoulders might be the best style. These classic styles with either a centre or off centre zip has up-side-down (inverted) triangular shape in very rough terms so it visually creates an image that this from the shoulders down, very clever in effect.
This is where the body widens at the hips; a designer style biker jacket that is reasonably box cut or straight cut tends to work better here as it will remove emphasis from narrower shoulders to wider hips and make the body shape look more even in width and this narrow the hips. It would also need to be a longer length style that came to the hip bone.
Hours Glass Figures
This tends to be women only. Whatever size label you are, if you narrow at the waist and your chest and hips are reasonably equal in width then a figure hugging style will draw out your assets. In reality you can have your pick and just select what you like best in most of the women's ranges. However if you are long in the body then a designer or longer length jacket might be better suited to your proportions, but if you are clever with what you wear then a cropped jacket can give the illusion of a longer length length and shorter body provided you are not teaming it up with hipster trousers or skirts.
Broad Shoulders & Narrow Waist
This is the male equivalent of the hour glass figure, what we can also call the 'Adonis' shape. If you tapper (i.e. narrow) from your shoulders or chest down to your waist then any of the men's biker styles will look great, so have your pick!!
With the continuing array of enticing fashion themes and and re-harnessing of classic designs created and available the biker jacket will continually be in the limelight of men's fashion. Individual styling extends a wide range and choice of fits, colour and leather finishes ensuring the design does not fade as a staple wardrobe favourite. New colour choices extend from the dark brown, tans and reds to taupe (beige / dark cream) aubergine (purple), white, greens and blues.
So all in all you can be relaxed and reassured in your choice of any style that you may fancy or select as it will most certainly serve well as a fashion accessory or statement on classic or chic and individualistic style. And most, most important, whatever your choice always enjoy it and wear it with pride.