You may opt to put the 9 iron, wedges and the putter into the small bag while the rest of the clubs remain in the larger bag. With this combination of clubs in the smaller bag you would simply lift the smaller bag off for shots around the green or from sand traps.
You may wish to (as many people do) put your 150 yard club (perhaps the 7 iron) down through and including the putter in the smaller bag. Now, when you are 150 yards from the green, you just lift off the smaller bag and play through from the 150 yard mark until you finish the hole. Because you will have all the clubs needed in the smaller bag, you never need to go back to the cart during that hole.
If you are playing a course that restricts the carts to cart paths, you may opt to put all of your clubs in the smaller bag, with the exception of the driver and a few long irons. Because you’re restricted to the cart path and can’t drive to your ball, you may not be able to determine your distance to the hole or the condition of your lie. However, there’s no need to worry. Again, all you have to do is simply lift off the smaller bag, leave the cart and walk to your ball with your selection of clubs in the smaller bag. Because the clubs are in the smaller bag, you never have to guess what club you’ll need to make the best shot. Also, you will never have to lay clubs on the ground. They are in the smaller stand-up bag so you never, never have to worry about leaving clubs behind. After you play your shot, walk back to the cart and replace the smaller bag back onto the larger bag and ride on to your next shot.