You can access your inner wisdom by committing to a process of elevating your consciousness throughout the flow of your daily existence. This requires time and patience as it is rarely an expedited process.
Accessing your inner wisdom can be conceived as an "awakening" or a "reintroduction" with one's self---so many people suppress the relationship they have with this aspect of their personality (i.e. that inner, instructive voice) for being overwhelmed, distracted or consumed with pursuing selfish wants.
Begin to elevate your awareness with a commitment to daily prayer and meditation. If you feel as though you lack the discipline to stick to it, pair up with someone or a group at the same time and place every day. Expand your thinking beyond yourself to silently consider your place in the grand scheme of the Universe; give thanks and praise for the gifts and blessings bestowed upon you; and express gratitude for the beauty of all you survey.
Gradually lengthen the amount of time you invest in this process. If you start out with only a few minutes at bedtime, expand this to include a few moments after supper or early in the morning when things are quiet. In time, you can extend this way of thinking into a state of perpetual meditation, or thoughtfulness, throughout the day in how you conduct yourself in all your interactions.
Accessing your inner wisdom may also bring unexpected benefits in the form of revelations for gifts or traits unrealized, such as a heightened intuition or a greater empathy and compassion. Accessing your inner wisdom is your birth-right; tap into it with reverence and regard, and a desire to serve others through its employ.