There are many excellent programs and resources out there concerning grip. Let me tell you though, I don't train grip any more. I will go back and work on wrist strength if there is an imbalance or if I am messing around with the Rolling Thunder for kicks. Otherwise, it’s become second nature for me. You have to work to get there. My results could very well be due to my man hands but I have heard solid feedback from some who have incorporated some of these ideas.
First of all, lose the straps. Go back to the idea of no gear and develop your body. When I started competing, gear was frowned upon. If you’re not strong enough, get stronger. Period. If you must use straps, only pull them out for special occasions like car deadlifts for reps or something more maximal once in a while. Otherwise, there's no need to be using them. Every workout that you are using straps is a missed opportunity to be indirectly working on your grip. I still haven't learned how to use straps and go figure, my grip is pretty solid.
Next, train with only the axle. I spent 2 years strictly training with the axle, no bar. Nearly all events in strongman use an axle so learn it well and train with it. When I transitioned back to a regular bar, it took me some time to relearn body positioning but I also saw increased lifts. Now I am able to transition between the bar and axle seamlessly. If I’ve gone too long without using the axle, there is a discrepancy in wrist strength with my hands.
When I started out training, it was drilled into my head to never end a workout without training grip. The Catholic guilt would kick in at the end of every workout that cutting corners would only hurt me in the long run. After a grueling event training day, deadlift or pressing day, doing grip is easy and quick. It should be as quick as stretching and is a great way to cool down.
At the end of every workout, use a wrist roller. I made mine out of 2 1/2" PVC to mimic the diameter of an axle. Roll it 10 times up and 10 times down for three sets. Start with a five pound plate and then keep adding. Make sure your arms are straight out in front of you and resist the urge to let your arms start falling. As you become more proficient, stand on a bench to increase the distance you need to roll. When your arms get tired, use your mind to help you gut out the last reps.
Train farmer's static holds for time. Find a weight that you can hold for 45 seconds and learn to love the feeling that your arms will rip off at any second. Use this time to learn the art of blocking the pain and how to mentally detach. This truly is an art form and you will find it comes in handy on other events. Once you are able to hold the weight for a full minute, increase the weights. The longest I would do static holds was 75 seconds but then the next workout I would increase the weight.
Finally, go buy yourself a set of dollar store grippers. I left one in my car and one in my desk at work. While driving I would pull it out and hold is shut as long as possible. I would challenge myself to make it through a part of a song, a whole song and then multiple songs. At work I would pull it out at every opportunity and hold it shut for time. When I would get bored with it, I would challenge people to a friendly competition to hold for time. I would let my students use two hands to hold it shut while I only used one. Otherwise the competition would be over pretty quickly. Again, this is an opportunity to train the mental piece, breathing through the pain and perfecting the art of detachment. Make sure you do this with both hands. My left hand was always weaker than my right so I would challenge myself to try to make it to the same time as my right hand.
I hear people say their grip just gives out in an event without warning and they have nothing left. I don’t know that feeling. I’ve learned to listen to my body, identify predictors of failing grip, work through the pain and develop mental strategies to hold on for just a little longer. Seconds count in strongman so get out and start working on that grip. You will be glad you did and the investment you put into your grip now will carry far into the future.