How to Find a Better Strongholds Mod Stronghold
Locating the Structure
Better Strongholds replaces the vanilla stronghold with a much larger, more sprawling layout, so the old trick of digging straight down at a triangulated point still works, but you should expect the structure to extend far beyond where you first break in. Throw Eyes of Ender as usual and follow them until they dip underground. When they start descending, dig down carefully rather than straight through, since the redesigned stronghold has multiple floors and you may punch through a ceiling into a room below.
Planning Your Descent
Because the mod makes strongholds bigger, the nearest entrance is not always the closest to the End portal room. Bring plenty of torches, blocks, and a way to mark your path, because the corridors branch heavily and it is easy to get turned around. If you are playing with other world-gen mods, the stronghold can intersect caves and ravines, which sometimes gives you a free entrance but can also flood sections with mobs. Once inside, resist the urge to sprint; the layout rewards slow, methodical exploration so you do not miss side passages that lead toward the portal.
What to Expect
You will find far more rooms than vanilla, including libraries, prisons, and hidden chambers. Treat the first room you enter as a base camp and branch out from there rather than wandering blindly.