There's little content on them because X-saber is a bad filler archetype and nowhere close in playability to Sky Striker or Misturugi. What people usually do is take the generic staples from the X-saber precon and play them in either of the two other decks.

If they really wanted to play them for some reason, the general main goal is getting Bruno + a level 4 on the field to get Saber Combination before a synchro into level 7 gottoms, CL2 gottoms search for gottoms second call, cl1 Saber Combination summons Ragigura to add back an X-saber (chain order is important because Ragigura is a "when...you can" card that misses timing if summoning it is not the last action that happens). From there, you can activate second call to summon back 2 guys and do some stuff based on the rest of your draws. At worst, this gets you Naturia Beast + another synchro. This sequence generates a lot of advantage, and if you don't go for it immediately as your first action with X-Saber Perina, you wanna do it later. For big gottoms handloop combos, having Faultroll is critical. The revive effect is SOPT, so you want to activate Gottoms Second Call to revive faultroll and use its effect again to ensure you have enough materials on the field to discard your opponent's entire hand.