The majority on this forum seem to think MILD stands for Mantra Induced Lucid Dream. If you're just repeating a mantra then it's not MILD, it's just autosuggestion. LaBerge makes a distinction in Exploring the World of Lucid Dreaming: "While using autosuggestion during the first sixteen months of my study ... I recalled an average of five lucid dreams per month with a range of one to thirteen ... With this new method (MILD), I had as many as four lucid dreams in one night and as many as twenty-six in one month."

The key aspect of MILD is recalling a dream you've just awoken from and visualising yourself back in the dream becoming lucid. LaBerge also recommends continuing the fantasy and imagining what you would have done if you had become lucid, combining the visualisation with focusing your intent until you fall asleep. If you adjust what you have been doing to what LaBerge recommends then hopefully you'll see a drastic increase in the amount of lucid dreams you have!