I learned something today from this thread. I'd never thought of using the SoapCalc calculator to scale my recipe size, and had built an entire spreadsheet to do the work for me, then checked the new figures against SoapCalc. Now I can stop using my spreadsheet, without a tear lost...
To add a little more to what others have already said, I measure each liquid fat in its own little pitcher, and sometimes do that for my solid fats as well, but as I've gotten more experience, I now frequently weigh the first solid (say: coconut oil) into a pitcher, then zero the scale (tare weight) with the pitcher still there, and start adding the second solid fat (say: shea butter). Since I can scoop a little back off if I add too much, there's far less risk of making a mistake than if you were to try the same trick with two liquid fats.
As a fellow new soaper, I can tell you that one of the best things I did was start wearing an N95* mask while mixing my lye water. I mix my lye outside most times, so that I don't have to worry about the fumes in the house, and always wore eye protection, long sleeves, gloves, etc. while mixing it up, but discovered that I'm very sensitive to lye fumes, even outdoors. You should have seen me holding my breath, stirring for a few seconds, stepping away, catching my breath, then heading back in to stir some more. One day I grabbed an N95 mask that I'd bought for use while sanding wood (wood dust is horrible for you), and added that to my 'soap lab' getup... total game changer. Now the lye fumes don't bug me at all. Once the temperature of the lye water drops, the fumes don't bother me, so I only wear the dust mask during the first mix, but I wear my apron, lab coat, safety glasses, and rubber gloves during all the rest of the soap mix process.
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Here's some advice you didn't ask for, too; if you are on a tight budget (and who isn't?), you'll have to make decisions about where to spend money: after you make a couple of batches and decide that this is a craft you want to continue to pursue, I suggest spending a bit more for a decent immersion blender (you don't have to break the bank, but spending a bit more than the minimum will help prevent you having a burned-out blender motor in the middle of a batch), and buy a scale that will do tenths of a gram.** The increase in accuracy is very reassuring when you're making small batches in particular. I haven't seen a lot of discussion on the forum about what scales to use, so I may be in the minority on this point.
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* I haven't tried it, but I imagine that a KN95 mask would help almost as much. After the pandemic, a lot more of us have stuff like this around our house, so you may not even have to buy anything.
** I have an even more expensive scale/balance that does hundredths of a gram, but only use it for weighing scents, powders, preservatives, and chelators, as it's too sensitive for bulk fats. I doubt this would be of much use to most people and I can't recommend it as a 'must have' item. My wife works with scents more than I do, and she has a balance that goes to three decimal points... far more accuracy than I'll likely ever need.