To answer your comment from the other thread, clippers can wrok to an extent, but they don't get close enough. I use clippers to remove a model's bits from the sprue and then a knife to cut the flash (the excess left sticking up from the part you want) away.
A knife is also good for shaving off mould lines, which clippers cannot do.


The very, most aboslute basics of painting are:

Undercoat - either white or black usually, using an aerosol primer for the most part (it's faster and proper primers have a different composition to normal paints). This is a must as it will stop your paint from chipping at the slightest touch and the colours will show up nicer.

Base coat - the primary colours blocked out*:

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Shading and highlighting - As illustrated above the colours are very flat. What are either called inks, washes, ink washes or shading** is used to darken the recesses. Washes are basically very watered down paints, so they flow into the darker areas and create shadows:

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Note the fur in particular:



Highlighting is creating the opposite effect - making the raised areas brighter. This is done either through line highlighting - painting the highlights on with a lighter shade, or drybrushing.
Drybrushing is my preferred technique, so I'll leave line highlighting up to someone else ;) to drybrush you get a larger brush, put paint on it then brush most of it off. Ideally you'll use an old brush, or a specially designed drybrush (they look like miniature shaving brushes).
The technique is to lightly dust the raised areas of the mini so the paint only sticks to the raised areas.

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If you note the very edges of the scales on her 'armour' you'll see they're very silver. I painted the armour black then drybrushed with a dark gunmetal and a lighter coat of silver




For consistency, here's the first mini finished - you can see some of the highlighting on her thighs and abs in particular.





Now, if you want to be quick and dirty, you can just do basic colours and an ink wash to shade and call it a day - its a very common thing for guys painting seventy bajillion orks for an army.


* the base colour is, after shading and highlighting, effectively the mid-colour. There are fancy tricks and techniques that involve using completely non-logical colours for the base, but I won't go in to them

** Inks, washes and glazes are actually very different in how they shade things, but they're close enough for now.