“… a more inviting way to enter meditation includes first learning the art of feeling good intentionally, in the present moment. We need to feel enlivened early in meditation in order to want to stay with it. Mindfulness needs to feel refreshing to ensure the future practice of mindfulness. If we are as unhappy in meditation as we are at other times, except being more aware of the unhappiness, where is the incentive to continue?
In my experience, the more reliable way to introduce safety, comfort, and trust in meditation is by evoking memories that elicit the feelings needed to create the foundation for our practice. Trying to think our way into feeling good is futile. Relaxation is one of the most fundamental aspects of the internal holding environment.”
Bill Morgan. "The Meditator's Dilemma: An Innovative Approach to Overcoming Obstacles and Revitalizing Your Practice." Shambhala, 2016.
Remembering a childhood experience was a powerful opening for the Buddha:
“ ‘While my Sakyan father was busy and I (as a child) was sitting in the shade of the a rose apple tree, then quite secluded from sensual desires, secluded from unprofitable ideas, I had direct acquaintance of entering upon and abiding in the first jhana-meditation, which is accompanied by thinking and exploring, with happiness and pleasure born of seclusion. Might that be the way to enlightenment?’ And following that memory came the recognition: ‘That is the only way to enlightenment.’ ” MN 36 http://www.accesstoinsight.org/lib/authors/nanamoli/wheel017.html
A powerfully-reassuring childhood memory may even be somewhat hazy - like this:
Perhaps my father, a certain aunt, one of my grandparents, or perhaps even a composite of these nurturing caretakers instilled within me a deep, quiet sense of certainty, that no matter how bleak and miserable life might be, even for decades, ultimately, everything will resolve in a decent, loving way. Perhaps that's why I value persistence so highly. I don't hope, but intuitively know that mystics and saints see things clearly.
Recalling this feeling is a powerful way for me to start meditation.
Find your own reassuring childhood memory.