Make sure your fork sag is set properly and slow down your rebound setting. The fork should sag about 25% of its travel when you are seated on the bike. If you have a 100mm travel fork, it should sag 25mm with you on it. Adjust the air pressure in the fork until you get the proper amount of sag. You can use a zip tie on the fork leg to see how far it sags. The rebound setting on the fork controls how fast the fork bounces back after hitting something. Slow it down so the fork doesn't instantly transfer the shock to the handlebars. You'll have to experiment to find the right rebound setting for your terrain. Too slow and the fork won't rebound fast enough to keep it from packing up(becoming progressively shorter and stiffer) on successive hits. Too fast and it will transfer the shock to the handlebars.