Before you adjust you soil pH, you have to find out what it actually is. Get a soil test before making any adjustments. You soil may already be perfect for blueberries and you don't know it.

Blueberries are very shallow rooted plants, the wild ones around here grow on hummocks of soil above standing water and they do not want their roots wet but they do want water close. A gross misconception is that sand will help clay soils, or that clay will help sandy soils, and if enough is added, anywhere from 45 to 75 percent sand, it may, but your best, and cheapest, way to amend your clay soil is with organic matter.
Tree leaves, Oak, Maple, Beech, Birch, etc. all test out with a pH in the 3.0 to 4.0 range and that stuff does not change a soils pH significantly so there is no really good reason to believe that any other organic matter would significantly change your soils pH either. All of the Blueberry Growers along the west shore of Michigan have their fields of blueberries in full sun, and the blueberries that self seed do so in full sun. Many of the blueberry growers have sand for soil and many have clay for soil, and few, that I have seen, amend their soil, they just pour a lot of water on the growing plants. Although most also grow grass between the rows and mow that leaving the clippings in place.

I'd skip the sand also. If you feel you need to bump up drainage, add some fine or ground bark to the planting area. The cottonseed meal will offset any possible nitrogen tie-up. FWIW, there is an old, established, commercial blueberry farm in my area (on the local historic register) that is actually on a bog - very moist, peaty ground. Still very productive after 75 years.

Thanks for the info!!! The soil is around 6.2 right now and is not very well drained. I have lots of white oaks around the planting area so I will just incorporate a bunch of those leaves in when I till the area along with the peat and cottonseed meal.

Is the composted acidified cotton burs a good option for mulch???

The soil here is acidic and so wild blueberries abound. In areas where gardeners have planted blueberries for their personal use, the soil has been neutralized by using compost, hence the reason for them to apply a bit of Ammonium Sulphate in the spring. You can look into that as well.