Practicing Krishna consciousness without a spiritual master
We all need the guidance of pure devotees if we want the full fruit of devotion to Krishna. We need practical guidance—according to time place and circumstance—how to proceed along the path of Krishna's service, and clearly understand Srila Prabhupada's teachings.
The same is true for any kind of study. If we want to learn piano, it helps to have a teacher who can see where we're at, see what we may be doing wrong, and correct us so we can advance. Private practice and studying books on our own will surely help us make progress, but having a teacher observe our progress firsthand and guide us step by step makes a huge difference. When we're eager to advance in our spiritual life, Krishna speaks to us through His devotees—especially the spiritual master—to help us.
Each of us needs to develop our own steady practice of bhakti which should include a thorough study Srila Prabhupada's books. When you do that, Krishna will lead you to a spiritual master eventually and you will be inspired to formally take diksa, initiation. But patience is recommended. Steadily practicing Krishna consciousness, reading Srila Prabhupada's books, taking the association of other devotees and coming to the temple are the recommended procedures for making quick progress on the path to Krishna.
It's most helpful to hear from devotees more advanced than yourself. This is how we become inspired in spiritual life. You can hear classes by many mature devotees on ISKCON Desire Tree. You may find by hearing from a wide variety of sources that some devotees especially inspire you in your Krishna consciousness.