Take the struggle only “one day at a time.” Try never to focus on the future or wonder how we will manage. We must learn to live in the present only, focusing on staying sober right NOW. When we focus on the future, we can easily fall. It’s like someone walking a tightrope; if he looks down, it becomes so much harder not to fall. Therefore, when feeling weak we can tell ourselves, “just for today, I will stay clean.” “Just for this moment, I will stay clean.” The past and the future are out of our hands and belong only to Hashem. When we feel that we are about to fall, we may even tell ourselves that we reserve the right to act out tomorrow. We are not making a decision now for life. However, just for today we will do whatever we can to stay clean.
One guy writes: When I get up in the morning after saying Modeh Ani, I always pray to Hashem in my own words and say something along these lines: "Hashem, I cannot control this without your help. I am willing not to act out on lust today, but I cannot promise about tomorrow. Just for today Hashem, please help me succeed."
This is one of the big Yesodos in the 12-Step groups as well. On any given day, if we do what we are supposed to on our side to try and stay sober and sane, we trust completely in Hashem that he will give us 24 hours of relief - for that day only.
We see this idea in the Torah too. The B’nei Yisrael were starving and needy in the desert. Hashem gave them relief for one day at a time. No matter if they gathered a lot, no matter if they gathered a little, they only got 24 hours of relief.
And remember, today is the first day of the rest of your life! So let’s do our very best to stay clean just for today.

and here we get to one of the most important ideas in this handook and all over GYE ONE DAY AT A TIME
when we look / think about tommorow and about what we will be like then, its so much harder to not fall. when i do that i take my energy that i have invested in today and start to put it on tommorow instead. how is one person supposed to count to 5 without starting with one? you can, each and every day becomes super important. day one is just as important as day 10 or day 50 or day 90 or even just as important as a whole year! even tell yourself, ill keep clean today and have a fall tommorow, tell youself that everyday.
skipping to small paragraphs,
in the midbar, everybody got enough mann to last them one day and only one day, hashem gives us our sustanance/ success, etc one day at a time