I share with you a simple system to build garage storage shelves. To build these shelves, you need some of the tools i have listed below. Further details on how I build these storage shelves in my garage are below.

Links to tools used:
My Bluetooth HEARING protection: https://amzn.to/3NWJzlc
Stud Buddy stud finder: https://amzn.to/2CdGQUz
Traditional recommended stud finder: https://amzn.to/3gZanQB
Spax 3” screws (star drill bit included…no pre-drilling): https://amzn.to/2AZ16bZ
Spax 2-1/2” screws (star drill bit included…no pre-drilling): https://amzn.to/2AWKHof
Kreg Pocket Hole Jig: https://amzn.to/3foCXKN
Kreg Face Clamp: https://amzn.to/3gSrKlY
4 Foot Level (must have): https://amzn.to/3j9L2p9
Makita drill (battery not included - owned 4 years…love it!): https://amzn.to/308AiP5
3M Ear Protection Work Tunes (bluetooth for music): https://amzn.to/2OomcDB
Face Mask (definitely use when cutting MDF!!): https://amzn.to/32hOaJu
Corded Circular Saw: https://amzn.to/2Czxz9f
Rafter Square: https://amzn.to/3j7S6Cj

Overall dimensions of these garage shelves is 18 ft long x 23 inches wide x 7 ft 5 inches tall. Overall cost for these storage shelves roughly $220.00 - $65.00 (sold metal shelves)= $155.00 (cost increased by spax screws, cost decreased by using MDF shelves & 2x3 when able). Depth determined by garage opening. I watched numerous garage storage shelf builds before doing this. When you are planning this out, definitely take into account the "stock" sizes that are sold at your home center. This will help determine where you put vertical supports. In my case, I did an 18 foot long shelving unit because of the "stock" 8 foot and 10 foot 2x4's I could buy at home depot (they also have 12' and maybe even 16' lengths). I used the system that Ana White introduced in her popular video:    • How to Build Garage Shelving - Easy, ...  . I saw a lot of simple, straight builds. I used concept of hers to build a full wall of shelves with different levels to work around a mailbox that protruded into garage and two windows. Feel free to ask any questions in comments. I can't think of a better system out there for your project!

Materials:
(20) 2x4 8 Foot studs
(8) 2x3 8 Foot studs (these were for the smaller upper shelves)
(2) 2x4 10 Foot Studs
(4) 4'x8' 5/8" MDF sheets
(2) 100 pack 3" SPAX screws (Didn't use all)
(1) 100 pack 2 1/2" SPAX screws
1-1/4" drywall screws (approx. 30 used)
Cut List:
(4) 36 1/4" 2x3 (over windows) 4x8 MDF: (6) 22.5" 8 feet
(2) 34" 2x3 (2) 24" 8 feet
(2) 39" 2x3 MDF: 24" used for top shelves (extend slightly beyond frame)
(2) 25 1/8" 2x3 22.5" used for lower shelves