How did Lincoln increase the size of the northern military?

Lincoln increased the size of the Northern military primarily through the implementation of the Enrollment Act of 1863, which established a draft to conscript soldiers into the Union Army. He also called for volunteers, leading to a surge in enlistments, and worked to improve recruitment efforts through Propaganda and incentives. Additionally, Lincoln encouraged states to raise their own regiments, further bolstering military numbers. These strategies collectively helped expand the Union's forces significantly during the Civil War.