I made a reversible apron recently (modified a commercial pattern) and would send you the deets but my sister scammed it from me already.
Try this though. Look at this free downloadable Burda pattern. http://www.burdastyle.com/patterns/show/1351
So, to make it reversible, all you do is cut 2 of the main apron and pocket piece. For mine I used black denim for 1 side, and skulls and roses fabric for the other. I used the opposite fabric to trim the pocket to spice it up a bit.
To sew reversible apron:
1. Sew the pockets to each apron piece.
2. Sew your straps and turn inside out.
3. Baste on the straps. You may need to adjust the strap placement marks. If you are doing 5/8 inch hems you want the outer corner of the strap to be 5/8 inch from the top and side of the neck corners and back corners. Place the straps right side down on one of your apron pieces - you want the raw edges together so the straps lay across the right side of the apron. Baste in place.
4. Pin the 2 apron pieces right sides together, making sure that the straps are tucked safely between them and not caught in the pins. Stitch together, reinforcing over straps, and leaving a few inches open on the bottom to turn.
5. Turn right side out, press and stitch opening closed.
I personally like adjustable neck straps, it makes me mental when the top droops. You can either make 2 straps to tie in the back, or do the d ring route. To do this make a strap piece about 3-4 inches long. double it over and slide on 2 D rings - 1 1/2 inch should do, depending on your strap width. Baste in as for one of the straps.
Also, I like an apron with sides that wrap well around rather than just coming to my side and then having a lot of strap across the back. You may want to check where the pattern is hitting you and add a few inches before you cut your fabric.
If you want one that has trim and ties like your example you need to insert the trim between the 2 pieces before you stitch them right sides together. I would think that the side that has the thinner strap across the front is the actual stitch that in place on the right side of the 1 piece. The other one has a wider band, stitch it in the same place on the other piece of fabric. When you sew the 2 pieces together they will match up and the strap will look like it comes from both.
Sorry if this is confusing, if you are still at a loss let me know and I'll try to sketch something up for you. Will also try to get pictures of mine, it's in the darkroom at school thought so it will take a few days.