Your timing is not the best. The best time would be when it was completely dormant. But, if you can get a big enough root ball, it might work. Prepare your new planting spot before you start digging it up. Mark an area the size of the diameter of the shrub. Dig in some compost.
To dig up the shrub, try for a root ball the width of the drip line. Remember to go deep enough. Hopefully, the rootball will stay intact but that's not always the case. If the soil does fall off, suspend the shrub over the new hole at planting depth and carefully fill in around the roots, try not to disturb them too much. Its those fine little roots that are feeding your plant. After planting and watering, do some pruning. No matter how hard you tried, you didn't get all the roots. The top and the bottom support each other and right now, having more roots than top will help your plant recover more quickly. Water until your newly planted shrub is floating - than keep it damp until you see new growth.
Its not hopeless; my husband and I once transplanted a mature mandarin tree. ALL the soil fell off and the tree did fine. The important part is to get enough roots and then preserve the health of the roots.
Let us know how it goes.
Daisy
