I tend to phrase all affirmations in the present because there is only the eternal NOW and time is an illusion. "Going to" might imply it isn't here when everything actually is right here, right now but not visible to the senses instantaneously too often because we're experiencing a time-space illusion and the "unfolding" makes things a little interesting. But ultimately it isn't the exact words that matter but the emotional state it evokes, that is the key because that tells you where you're generally focused regardless of what you're affirming. Typically though, as long as you haven't built a too negative world view, you should get comfortable (: that's good :) using the affirmation and then you're good to go. I use affirmations more as a tool to guide the mind and remember my broadest intentions rather try to "make" myself belief anything that way I avoid inner conflict. So it's more like rather than think a negative thought, I might as well think this positive thought that reflects my intent even if I don't believe it fully.