Reciting psalms on Rosh Hashana



I heard it is important to read the Book of Psalms twice on Rosh Hashana because the 300 psalms numerologically equals kaper (atonement). If I join a group that is reciting the entire Book of Psalms on one day, is that considered as if I said the entire book or do I have to say the whole Book of Psalms by myself?


If you can say the entire Book of Psalms yourself that is preferable to joining a group saying it.

However, always remember that it is better to say a smaller amount with kavana, than a large amount without kavanah (Orach chaim 1:4).