'Soak' and 'dip' are completely different. If you soak something, it is totally immersed in liquid, often for a long time. For example, if you have a stain on a garment, you could soak it overnight in a bowl of water. If you are caught in heavy rain and your clothes are completely saturated, you could say that you are 'soaked'. 'Dip' is the movement of putting something into a liquid for a very short time. You can dip a biscuit into your coffee, for example. If you want to check how much oil you have in your car, you take a 'dipstick' and dip it into the oil for a moment. If you say 'I'm going for a dip' we'd understand that you are going for very quick swim in the sea. In some ways, the two words are almost opposites, in terms of time and amount of contact with liquid.

Yes, 'clean' is the right word for what you do with shoes that are dirty. It's possible, but not usual, to say 'clean up'. The object of 'clean up' is usually the stuff which needs to be removed e.g. 'I must clean up that mess in the kitchen'. No, 'void' isn't the right verb. For a bottle of shampoo, a packet of rice, or anything else of that type, the verb you want is 'empty'. For example, if you are tidying up after breakfast, you would empty the coffee cups into the sink. For a hard drive, you could say 'empty', or more likely 'wipe' or 'clear'. 'Void' is not a common verb. It's used in the sense of 'empty' in medicine/physiology, and also in other technical and scientific fields, but not in everyday English.

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