The Twist TrueAmp Library Preparation Kit integrates enzymatic fragmentation with end-repair and dA-tailing into a streamlined workflow, allowing fragment size distributions to be tuned through adjustment of reaction parameters such as temperature and incubation time. In this technical note, we systematically evaluate how fragmentation conditions within the Twist TrueAmp Library Preparation Kit's workflow influence insert size, library yield, and sequencing outcomes. We further assess the role of SPRI bead-based size selection at key workflow stages to refine library size distributions and improve consistency. We examine downstream sequencing effects using shallow whole genome sequencing (WGS) on the NextSeq 550 platform. Finally, we evaluate the impact of DNA storage buffer composition on fragmentation and library yield when using the Twist TrueAmp Library Preparation Kit. Together, these results provide practical guidance for tuning enzymatic fragmentation conditions to generate high-quality libraries tailored to specific sequencing applications.