1. Increase the diameter of GC, 7F GC has stronger support than 6F and can also complete standard CRUSH and DKS, but it is usually completed mainly via femoral artery and is generally not used for radial artery. 2. Deep GC insertion can obtain active support, but sometimes the right coronary GC insertion is too deep, at this time, another 0.014 guidewire can be sent to the GC outside the aortic root in a U-shape to prevent GC insertion too deep and stabilize the GC; sometimes the left coronary GC overshoots LAD or LCX, at this time, two guidewires can be sent to LCX and LAD respectively, which can prevent GC overshoot and increase the support of GC at the same time. Yao Yucai, Department of Cardiology, Shandong Qianfo Mountain Hospital, Shandong Province, China 3.5F in 6F can provide strong support, especially suitable for transradial route, note that it is safer to push along the balloon catheter to prevent damage to the coronary artery when feeding 5F GC. 4. Feeding multiple guidewires to the distal end can provide strong support and stabilize the GC; sometimes a strong supporting guidewire can be fed into the proximal branch of the lesion to stabilize the GC and increase coaxiality and support; sometimes a small diameter balloon with low pressure (2-4 atm) can be fed into the proximal branch of the lesion to dilate and anchor the GC to increase coaxiality and provide a stronger support.