We’re taught that if one is forgiving of others, Hashem will be forgiving.
Here are things to be forgiving of in Shul this Rosh Hashana
1) Time davening is over
2) Niggunim chosen by the Ba’al Tefillah
3) Temperature in the Shul
4) Length of the Rav’s drasha
5) Kibuddim you received
6) Someone looking at a sefer you brought
7) Childcare services