This website had very good instructions for making this bag and I think that our bag turned out great! However, we DID make some changes so if you would like to learn how to make an AWESOME tote that is big but has longer straps than the one in the picture on the left then keep reading! :)
HOW TO MAKE AN AWESOME BIG TOTE
2 pieces of fabric 24" x 21.5" or 1 piece 48" x 21.5" (to be folded over) for the bag
2 pieces of fabric 47" x 3.25" for the straps
2 pieced of Pre-Cut interfacing 1.5" wide
My mom and I decided to cut 1 big piece of fabric and fold it over instead of worrying about pinning and having 3 edges to line up! :)
It's now time to move onto the straps! This original post did not mention whether or not they used interfacing so I am assuming that they did not, well...we did. To make the straps, cut a piece of fabric the length that you would want them, and width of 3.25 inches.
Fold over about 1/8 of an inch onto the interfacing on each side and iron until there is a crease so that your raw edges will be hidden.
Once you have a crease on each side, fold the strap, with interface inside, in half so that none of the interfacing is showing and iron to have a finished look. (Hint: If you can have an extra hand to push the iron along for you it makes the process a lot easier!) You will still have one open side to your strap so you will need to pin and go over to the sewing machine and close up the strap with a doubled straight stitch. Once you have done that your straps are complete!
**Below is a gallery of step by step how to do the straps**
The next step to this bag is to create a finished edge at the top of the bag. All you have to do for this is fold down the raw edge at the top of the bag, pin it down where you want it, and sew!
Once you have created a finished edge for the top of your bag you are ready to complete the FINAL STEP!! :) Attaching the straps is the last step, to attach them, measure out how far down you want the bag to hit you by holding the bag up to you with the straps. Once you have got your bag at a comfortable length pin them to the inside of the bag and sew them on, my mom decided to sew all the way around the strap so that it was like a square for added support.
When you have sewn on your straps you have finished your bag! Turn it right side in and check it out! You're ready to go to the pool!