I wonder why this is in the "photography" area.

First, determine what color range of beads you have available in a single size.

Decide whether you will use a through-the-beads-twice method or a double-twisted warp. It makes a slight difference on the height x width beadcount.

Decide whether you'll use beadwork software or hand-draft your pattern. One method is to print a bead-scale grid on transparent plastic and place it over the picture or drawing which you wish to convert to beadwork.

If you're using software, follow the chart. If you're hand-drafting, create your chart and then follow it.

I prefer the twisted warp method and use weaver's cards in conjunction with fishing swivels for the warp-twisting. I use the finest thread that's of suitable weight when doubled. No matter what one does, it will be doubled through the needle's eye so I just use doubled entirely for the woof (which holds the beads).

If the warp is spaced with a spring, stretch and position the spring so the warp will fit the chosen beads. It won't be the same for #14 as it would be for #10.

Keep your tension even rather than snug. Black beads are often physically smaller than white beads in the same nominal size. Avoid over-tightening.

I load one row of beads at a time, whether I'm doing twisted warp or more usual methods. With the more usual methods, I position the beads *under* the warp and then press them upward, the better to assure the woof will go completely over and completely under the warp, rather than accidently missing and have semi-loose sections.