The scale looks perfectly fine for what you are trying to do. Since you are going to handle small amounts of these compounds, I am not sure whether you need gloves, goggles and respirators - in my experience these devices cause more distraction and spills than they will likely protect you from. What you should have ready is a plan for emergencies: what do you do if you have a spill (powder or liquid)? Is there a water faucet near you where you can wash your hands and eyes if necessary? Could you clean up a powder spill in the room you work in without tearing apart your whole flat? Do you know whom to call/alert if something should happen to you? Can you ventilate your room in case smelly and/or toxic fumes are created in the process (shouldn't happen normally, but things happen once in a while).
Another thing you should look for: have enough spoons and beakers, such that you can measure and fill each ingredient with a separate spoon into a separate beaker. Sometimes you get too much compound into your beaker, and you can reclaim chemicals only if the beaker was clean before. Some compounds stick to your spoons, so you can't reuse them either, as washing and drying them between ingredients would be very tedious and time consuming. Also, think about getting a proper stir for your big beaker, since Sulfite doesn't dissolve very quickly and without lots of agitation. Don't even think about reusing these spoons and beakers for food or hygiene purposes, ideally you'd get beakers and spoons that you can tell from your regular kitchen ware.
Finally: expect to spend much more time on mixing than you'd normally think you'll need, start with one hour estimate for one batch of D-19. Some powder compounds (Sulfite, Carbonate) will take some time and plenty of stirring to fully dissolve, and the instructions usually call for dissolving them in the correct sequence and one after another - for good reason BTW.
Other than that: relax and enjoy the process - and the results!