If you are in the process of renting a storage unit and filling it with items you will need to access on a regular basis, you need to make sure that you set up the storage unit for regular access from the start. In order to do that, you need a plan.  

Use the Same Size Boxes 

First, you are going to want to use boxes that are all about the same size. Using similarly sized boxes will make it easier for you to stack up the boxes and arrange them. If the boxes are lots of unusual sizes, it will be more difficult for you to easily stack the boxes up and pull the boxes out when you need to grab an item.  

You may also want to consider using stackable storage bins that are made to stack on top of one another. You want the boxes to be easy to stack up and move around.  

Label All Boxes 

Second, it is extremely important to label all of the boxes. It is better to go overboard with labeling than to go under-board. Put the general theme of the box on all the sides and on the top of the box. For example, you could label boxes "Books" or "Susan's Winter Clothing". You can also, on one side of the box, tape on a more detailed inventory list. That way, you'll know exactly what books are inside each box or what winter clothes you have in each box. These labels will make it easier for you to find items when you need them.  

Create a Master List of Items 

It can be easy to forget what you have in storage and what is just lying around your home, which is why you should create a master list of everything in the storage unit. Create a list with all the boxes and what is inside of each box. You may want to also number the boxes so you can easily connect a box in your storage unit to the box on your list. It is also helpful to have a master inventory list for insurance purposes.  

Create a Layout 

Finally, create a plan for how you want to put the boxes in the storage unit. Put the boxes that you will need to access the closest to the front of the storage unit, and the boxes that you don't think you'll need to access as much near the back. Make a little blueprint to follow when you move everything into your storage unit, and keep this blueprint to make it easier to find what you need later on.   

If you are renting a storage unit that you plan on filling with things that you will need on a regular basis, use boxes that are similar in size so they are easy to stack on one another and also easy to move around. Label all your boxes, and create an inventory list. Have a plan for where to put the boxes, and keep the layout blueprint for future references.