I have copy/pasted a reply I gave a few months back to someone else about this. I call it the 10 Commandments of Web Modeling:

TL;DR A sort of 10 Commandments to BBW Web Modeling Depends on several factors... 1) Are you prepared to see your work stolen and posted online often? There are some girls who are able to stay vigilant and keep their stuff from getting ripped and torrented, but some always slips through the cracks. Also know that there are "promoters", webhosts, and other folks that will get in touch. Some are honest, but some could not be trusted to not steal the teeth out of your mouth. There are a lot of shady people in this business, so be careful. 2) Are you prepared to be told by many online commenters you need to gain MORE weight? They will tell you "Looks so good. but ud look great with another 200 lbs." or "imagine that belly down to ur knees, gurl". Be prepared to deal with so much of that. 3) Every part (and I mean EVERY part) of your body, from your hair to your toes, will be critiqued, discussed, scorned, worshiped, etc. Some random person could tell you your hair is stupid and you're not fat enough, another could tell you your skin is not perfect and you're too fat, and a third could say you are perfect and subject to his every fap. 4) Speaking of that: understand that you will become fap material for people you cannot even imagine exist. FA's and fans of BBW cam shows come in every stripe. You could have the nice, handsome, boy-next-door type admiring your pictures; you could also have the 55-year-old out-of-work Walmart greeter with bad breath, extreme back hair, and 7 day unwashed crusty drawers ogling your picture and dreaming about things to do to you that you never even considered. 5) Your privacy: if you are on any sort of personal social media, you will want to either delete it before you do this, or find some sort of way where your personal stuff cannot be found. Some folks on here will do everything they can to find out who you are IRL; most just want the dream of getting to meet you, but some are like Buffalo Bill in Silence of the Lambs and want to put the lotion on the skin. This leads to... 6) Also understand that unless you are in the upper tier of looks or have a unique shape that causes FAs of all stripes to lose their shit (examples would be Plump Princess, Big Cutie BoBerry, Foxy Roxxie, or Big Booty Asshley), you are going to be expected to engage in some fan interaction. Even some of your upper-tier girls engage in massive amounts of fan interaction, and unless you have a unique appeal, you'll have to do the same. At the very least, you will need to engage in online promotion (Dimensions, Fantasy Feeder, Fat-Forums, etc.). 7) Do not go into this expecting to get rich. This is not a business that will allow you to make money overnight. If you want to have success, you'll need to have a quality operation/website. If it looks crappy or doesn't work well, people will not buy. Also, don't forget outfits, props, etc. 8) If you have a partner (and most that are in that business do), make sure your partner reads this message as well, understands all of it, and most importantly, is still on board. You do not want this to break up your relationship, and this is something that has broken up more than a few relationships. Make sure they understand that you are with them and only them; otherwise, it will cause more drama than Days of Our Lives. 9) Set limits for yourself that are comfortable for you. Some people are comfortable doing "cheesecake" modeling (bra and panties); others, artistically nude, but never where you can see areola or genitals; some are comfortable with showing all, but no action; some are comfortable with toys; some are comfortable with men; some are comfortable with other women; some go all the way to DVDA (watch the movie "Orgazmo" for the reference). It all depends on what you are comfortable doing. You will receive pressure to go beyond your comfort zone. Stick to your guns and do what you want. 10) Finally, if you want to do this, and you want to be successful, make sure you love you. If you don't love yourself and/or are not comfortable in your skin (or that scenario), it will show, and word will get around. Ultimately, it is YOUR decision and YOUR body at the end of the day, so you are responsible for YOU, no one else. As a final note, make sure you don't rip people off on stuff, as word gets around quick, and the schadenfreude in this community is quite strong.