Romanov with Beads
This is a particularly beautiful byzantine variation but it can be kind of tricky and requires the ability to make a really good bead link. (I'll have a tutorial available for bead links soon but it isn't ready yet so you might need to search online for instructions in the meantime.)
One unit of Romanov consists of two segments of byzantine and one bead link, joined at each end with a larger connecting ring. A segment of byzantine consists of 14 rings (2-2-2-Fold-2-2-2-Fold-2). The tricky part is the bead link. It must have small simple loops, not wrapped loops, and the loop must begin right up against the bead with no visible 'neck', which takes some practice. Once you have two byzantine segments and a bead link made, open your large connecting ring and put on one end of a byzantine segment, one end of the bead link, then one end of the other byzantine segment and close the ring. Open another large connecting ring and put the other end of each piece on it in the same manner. If you have trouble getting it to fit or if the unit won't lay flat once it's put together, chances are good that the bead link is too long and must be remade. This is why it's so important to have the loop right against the bead.
Romanov can be made with byzantine segments of any gauge but you might have to play with it to find the right size bead to fit in the center. It's a bit easier if your chain isn't too snug. For your first try, I would recommend byzantine segments made of 18g/3.5mm rings, 16g/5.0 or 5.5mm connecting rings and 6mm round beads.
Romanov without Beads
Romanov without beads is made exactly as described above but without the tedious hassle of trying to make the bead link fit, so obviously it's easier. For fun, you might want to use slightly larger rings in the center of the byzantine segments. You can also connect those center rings to each other with the small rings for added visual interest. Ring size recommendations for a first try are the same as above, though this variation also looks really nice in smaller gauges.
The photo at the top of the page is a simple Romanov without Beads but it looks so striking with copper multistrand rings as connectors. This one is made with 16g/4.5mm sterling byzantine segments. Each segment requires 14 rings so 28 rings for each Romanov unit, which is 3/4 of an inch long when curved as shown. The last pair of rings at the tip of each byzantine segment is 16g/3.75mm. (That's what holds the curve in the byzantine segments.) The copper multistrand rings I used for connectors are 3x18g/10.0mm. I used 8 for an 8" bracelet, so plan on needing 1 per inch for this chain.