Brushes are prime breeding grounds for germs – and every make-up artist we’ve ever spoken to recommends washing them once a week. Use just a little gentle shampoo on the bristles and swirl against the side of the sink till the water runs clean. Alternatively, you can use a professional brush cleaner which will be solvent-based – but to be honest, even though most of the solvents evaporate after you’ve done this, Still prefer the old-fashioned washing-in-warm-water technique, which feels more thorough when done correctly.
Let the brushes fully air-dry before using; leave them to dry with their ends over-hanging the edge of the counter, resting on towel so they don’t roll off. (And maybe set a diary reminder on your phone for you to do this more regularly than oh, once every spring…)