I got the black background idea from
@IrishLass' profile pic. I use a black cloth ( dress in this case) draped over a chair (seat and back). Then position the chair so that it has a full light source facing it ( a window is fine if it's a clear day). Sometimes I take the whole thing outside on the patio to do it. Place your soap on it.
If you have a proper camera then set the f-stop to about 6, the ISO to about 200 (if inside then make it 400) or if it's extra sunny make it 100. It's not recommended to take any photos in full sun though - better to wait til the end of the day. Shutter speed varies depending on the other conditions.
If you use your phone, then just frame up the pic so that only the soap and the black background are visible, then touch the screen on the front piece of soap to focus it. Click.
ETA: Do not stand between your light source and your soap! Stand off to one side so you don't cast a shadow on the photo. And actually - you should be kneeling anyway, not standing - keep to the same height as the product you are photographing unless you are taking pics on the top.
@Todd Ziegler - for the top one I took a leaf out of Ione's book where I read that she uses 40/60 saturated unsaturated fats for her swirls. So I adjusted my usual recipe ( same ingredients pretty much but different ratios) to this:
OO 45%
CO 20%
Soy Wax 15%
RBO 10%
Castor oil 5%
Shea Butter 5%
Lye concentration 28%
However, for the bottom (pink and black) recipe I forgot to use what I cal my 'Ione Swirl' recipe and used my standard one. The FO was very well bevel so I still managed a swirl in that one. I used my usual recipe which is:
20% each: OO, CO, Soy Wax, RBO
10% Shea
5% each: Castor, Avocado oil
Lye concentration 30%
Because of the soy wax I tend to soap about 43-45 degrees celsius.
