What are some ways to prepare oneself for Holy Communion?
Here’s a quote from the CA online encyclopedia (newadvent.org/cathen/07402a.htm):
That Holy Communion may be received not only validly, but also fruitfully, certain dispositions both of body and of soul are required. For the former, a person must be fasting from the previous midnight from everything in the nature of food or drink. The general exception to this rule is the Viaticum, and, within certain limits, communion of the sick. In addition to the fast it is recommend with a view to greater worthiness, to observe bodily continence and exterior modesty in dress and appearance. The principal disposition of soul required is freedom from at least mortal sin and ecclesiastical censure. For those in a state of grievous sin confession is necessary. This is the proving oneself referred to by St. Paul (1 Corinthians 11:28). The only case in which one in grievous sin might dispense with confession and rest in content with perfect contrition, or perfect charity is when on one hand confession here and now is morally speaking impossible, and where, on the other a real necessity of communication exists.
The current requirement for fasting is one hour before Communion.
In a personal sense, when I stand in line for Communion I shut out the world from my mind and focus on the Personhood of God Who loves perfectly.