1. In high requirements, you should provide complete package for the inner conductor, and using coaxial connector to ensure the integrity of the electric field shielding.
2. vias: In high-speed signal, the via produces 1-4nH inductance and 0.3-0.8pF capacitor. As a result, the vias of the high-speed channels should be as small as possible. Make sure that the number of vias for the high-speed parallel lines is the same.
3. Stubs: Avoid using short lines at high frequency and sensitive signal lines
4. Star signal arrangement: Avoid high-speed and sensitive signal lines
5. Radiation type signal arrangement: to avoid the use of high-speed and sensitive lines, to keep the signal path width unchanged, the vias through the power surface and the ground should not be too intensive.