Living a spirit-filled life is like being on an inner tube river ride. You sit in a giant inner tube, and it takes you along a river-like current that you have no control over.
In order to enjoy the ride, you have to just hold on tight to your tube, and resist the temptation the hold on to any nearby sidewall that you can reach! The joy of the ride is found when you just let the current take you where it wants to.
I believe that's how the Holy Spirit wants us to trust Him. He wants us go with the flow of His Spirit and enjoy the ride!
It can be scary and there may be some unexpected twists, and turns, and yes, you will definitely need to hold on tight, and you will get wet! But being in the current of God's love is the safest place to be. He knows where He wants to take you and there are many lessons to learn along the way.
So don't hold on to the "sides", and definitely don't stand up! There is great freedom, and joy is found in just enjoying the ride and learning everything you can from the experience with Him! He will use everything you learn to bless someone else! That's always been His plan.