Next time you're in the shower, soap up your body last. Go ahead and turn off the faucet, once you've got a good balance of lather and steam, to make bubbles in the ring of your hands. Slowly make them larger, until the bubble is ringed by your arms, hands, fingertips barely touching, and chest. Watch the bubble's surface, the reflection of yourself stretch and writhe.
Take a breath, lift your hands over your head, still keeping the ring and bubble intact, and dive into it. Sometimes it helps to soap up your nose too.
The first time, I closed my eyes. I still close them, the transition is rough enough without having to watch it.
The first time, I came out of the other side of the bubble under water. I still do sometimes, but my aim is getting better.
The first time, I had to lather up my whole head, slick back my hair, and dislocate my shoulders. It still hurts, but it's worth it.
The first time, I couldn't get back.
They say some people can cross just by holding their hands out in front of them, index fingers and thumbs forming a ring. Through that ring is all most people see, all they can see, all they want to see. Focus on the ring, until something steps into your peripheral vision. Step sideways and follow it, keeping your eyes on the ring of your index fingers and thumbs. Step sideways through the veil.
The first time, that's how I got back.