There is only one day before the birthday. Will it be like the character of the next constellation?

If the birthday is at the boundary of the constellation. You can find out which constellation you belong to by looking up the "Fast Lookup Table of Constellation Edge".

Look at the proportion of your own constellation by looking at the degree of the sun constellation on the astrolabe. The house occupied by each sun sign is 360/ 12=30. 30 degrees is divided into three grades, each grade accounts for 10 degrees. Also known as 10 degree interval. The planet in the first 10 degree interval has the strongest strength, which can give full play to the characteristics of the constellation, while the strength in the second and third 10 degree intervals is weak, which cannot show the typical characteristics of the constellation, and will imply a certain constellation character (fire and geomantic omen) which is the same as the constellation elements.