Since his release from death row last summer. Damien Echols has found himself savoring the small things.

“Last night I sat on a park bench eating ice cream and just watched the moon,” he tells PEOPLE’s Johnny Dodd. In his new memoir Life After Death, Echols, 37, one of three men convicted of murdering three West Memphis, Ark, boys in 1993, opens up about the horrors of his 18-year incarceration-which ended in a plea bargain after a long fight to prove his innocence-and the hard-luck life that helped land him in prison. Now living in Salem Mass., with his wife, Lorri Davis, Echols admits that adapting to freedom hasn’t been easy. “I get overwhelmed with fear about getting lost,” he says. “Learning how to use the subway, an ATM card, the Internet-for most people, technology came in bits. For me. it came all at once.” But it’s a small price to pay, he notes, for the chance to build a life. “After all those years,” says Echols, whose memoir is excerpted below, “I’m finally getting to do the things I dreamed about.”

Echols grew up “dirt poor” with his mom, sister and abusive stepfather.

We lived in a shack for 30 dollars a month. No running water or electricity. Jack Echols was the first man to pay attention to my mother after my father left. Most of his teeth were missing. He pinched me until I turned purple, bent my fingers backward, and twisted my ankles. His excuse was that he was trying to “toughen me up.”

Turning as a teen to heavy metal, long hair and trench coats, Echols stood out in conservative West Memphis. After his arrest at 17 for trespassing while running away with his girlfriend, he met Jerry Driver, a police department employee who worked with juveniles, who became convinced. based on Echols’s appearance, that he belonged to a Satanic cult. The charges were later dropped but Driver continued to harass him.

Once he showed up at the front door. “I’m here to arrest you,” Driver wheezed. This was quite a shock, as the only crime I had committed was not being in school. I was put in chains and shackles like a convict, then left in jail for a few weeks.

On May 5, 1993, Stevie Branch, Michael Moore and Christopher Byers were murdered in West Memphis. Immediately police homed in on Echols, his friend Jason Baldwin and their acquaintance Jessie Miskelley; all three were found guilty, but only Echols was sentenced to death. Prison life was hell.

One night two guards handcuffed me and took me to the warden’s office. One held me up by the hair as the warden choked me. One of the guards kept punching me in the stomach while asking, “Are you going to tell anyone about this? Are you?”

[Another thing] you never get used to is that one day a man is there, the next he’s [been executed]. Insanity is rampant on Death Row.

In February 1996 Echols received a letter from Lorri Davis, a New York landscape architect moved by his plight after seeing an HBO documentary on his case. In trading letters, they fell in love. I knew I was in love with Lorri when I started to wake up in the middle of the night cursing her for making me feel the way she did. Without her, I would have died. We weren’t able to touch each other until December 1999, when we were married.

Daily meditation helped him as well, but by summer 2011 Echols’s health was failing, and he was struggling to stay sane. Then came the call: His attorneys had finally struck a deal that would allow him to go free.

People keep asking me what I was thinking the day I walked out of prison. The answer is nothing. I wasn’t thinking of anything at all, much like the day I walked into prison. The trauma was just too great. My 18-year-old son Seth [from a prior relationship] and I are slowly trying to bond. We don’t know each other, but we’re learning. When we talk on the phone, I have the entirely new and foreign feeling of being a father.

These days, I try to look forward. I’m tired of looking back. Ultimately, I know that freedom isn’t enough. The only way all three of us will be able to live the rest of our lives is by being exonerated. The person or persons who murdered those three children, and who put me on Death Row for eighteen years, need to be found and brought to justice.