Lindans, u gotta visualize it. That's all there's to it. Visualize one cut out at a time. If i take this positive sphere and i take this negative sphere. This area will overlap, thus cutting it out. creating.. this shape! yay! Then group it, render it and see the result, check if it's satisfactory, if not, move bits around. Once u got it right add ur next negative boolean or ur next positive one. Add it to the group to make it interact with the individual objects in the group. Or, if neccesary, group it with the group to have it operate on the group as a whole (if u want to have a booleaned shape to have a boolean effect on another shape for instance).

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