Setting precise guides in Illustrator can be a challenging task. There are a variety of methods that can be used, depending on the specific needs of the project. Here are a few tips to help you get started:
1. Use the Rectangular Marquee Tool.
This tool allows you to create precise guides by selecting a rectangular area on the artboard.
2. Use the Align tool.
This tool can be used to align guides along specific edges or lines.
3. Use the Free Transform tool.
This tool can be used to resize and move guides around the artboard.
4. Use the Snap To Grid feature.
This feature can be used to help ensure that guides remain in the same location across different pages or artboards.
5. Use the Auto Layout tool.
This tool can be used to automatically position guides along the artboard.