Model Master Tan

Painting tan is akin to painting yellow. Using a primer of some sort will help a lot and I like some sort of light gray, either primer or actual paint.
As far as glossy, what number is it? Is it a gloss or flat number? For instance FS33531 is a flat but if the first number is a 1, as in FS13531 then it's a gloss. Over coat accordingly to obtain what you want or change paint.

It's possible that your paint isn't thoroughly mixed. This may account for the poor coverage and glossiness. 

Use a suitable implement and stir the paint well. Continue to stir until there are no globs/strings and the paint is a uniform consistency.

Don't shake it - stir it. Shaking alone will not work, particularly if the bottle has been sitting a while and is well settled.

Try undercoating tans and similar colors with either white, yellow, or even red, depending on the shade of tan and the effect you want. Lighter tans have better hide than some whites, yellows, or reds, but often don't hide as well as similar shades of other colors.

Make sure the paint is thoroughly mixed and careful not to spray on layers too "wet" as this can make make the finish appear a bit glossy. Many light coats are better than one heavy one. And as the others said, light colors sometimes work better with a neutral  gray as a primer.

Also, if you do try to shake, a couple of zinc-plated bb's added to the bottle will help, although if it has settled, you will need to stir it at first.