As much as is necessary at the time.
SW differs from WW in that you don't have defined portion sizes. The plan recognises that what fills one person up won't even begin to scratch the surface for another person.
The plan relies on you to understand your body and to recognise when you are full (and therefore when to stop eating). But should you not be able to recognise the signs yet, it gives you the option to eat and eat and eat and still lose weight.
Try and break the habit of the WW portion sizes, put away the scales (except for your HEX's) and go by eye when putting things on your plate, eat until your full and then stop.
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