For me, and I know a lot of this has probably already been covered, but if I could go back 15 years, and give myself advice about soaping with what I know now is this:
-Always wear protection, (goggles, gloves, etc.,) at all times when there is a presence of lye around.
(Many people have heard my story about when there was a freak explosion down the street from me when soaping one time - if not, just ask, I'll start a thread about it - I WAS wearing protection, thank goodness because TRUE accidents do happen)
-Don't panic with an acceleration or seized soap. There are plenty of things to counter this if/when it happens. I used to freak out, panic, make things worse and end up in almost tears. Now, it's just like, oh, poo, okay here we go to fix it...
-Don't be afraid of color - I used to use tiny tiny little portions of color and could never understand why my colors would fade to almost nothing, or not be as bright as I anticipated. Now I use much more, and always get the colors I'm after (for the most part) but not so much it colors/stains wash cloths.
-You really don't NEED a lb of every fragrance you want to try, even if the price per lb is cheaper by the ounce than buying a sampler. When I first started I would always buy lb quantities of every fragrance I would purchase, sure I would "use it all fast" - no. Don't do that. Also, just because there is a sale on FO doesn't mean you HAVE to have it. LOL (I know, try telling that to all us FO-HO's!! LOL)
-You do not NEED every new mold out on the market, no matter how well priced, or how much you think you'll use it. I have so many molds that literally just sit there because I used them once, didn't like them, whatever. I literally use my ED molds, and my 5lb log mold and that's about it. (I have about 15 soaping molds - don't need that many!)
-Don't get distracted. If the phone rings while you are in the middle of a soapmaking session, don't answer it. Chances are it isn't going to be THAT important. If the doorbell rings, let them realize you are busy/not going to answer, etc., (I know emergencies do happen, but for the most part, you know what I mean...)
-Don't soap drunk or high. This seems like a no brainer, and no, I don't have experience with this, and have never done this, so basically I didn't need this advice when I started, but have heard stories and just cannot imagine the danger, and to help others thought I'd throw this out there - especially since recreational marijuana is legal where I am, and most likely will be around the nation within the next 5-10 years.
-Don't peek at your soap while it's "resting" - it will become soap without you looking at it every 5 minutes to make sure it's doing its thing. LOL I used to always unwrap my soap to look at it to make sure it was gelling, or doing, whatever, and it's just not needed. Now with more experience, I literally forget about it until it's time to cut the next day or day after. One time I literally did forget about it for like 4-5 days, and though it was going to be impossible to cut. It cut fine, it was just a little stiffer than usual, and I just had to go slower...
I think that's all the beginning advice I can think of at the moment, but I'm sure there is more I wish I would have told myself back then.