Loose skin after Liposuction, what can I do? (Photos)

Unfortunately, you may not have been a candidate for liposuction alone, but needed a tummy tuck and/or lifting procedure to improve sagging skin. You still have swelling, which can last 3-6 months after your procedure. I recommend adding hyperbaric oxygen and lymphatic massage along with your compression to help decrease swelling. To improve your final results, I also recommend adding vanquish for further fat removal, exilis/venus legacy for skin tightening, cellutone/z wave to make the skin smooth, remove scar tissue, and improve the skin’s appearance. See an expert. Best, Dr. Emer

There is an inherent tonicity to the skin which allows for elastic recoil when the fat volume decreases. 
Generally speaking, a good rule of thumb is "excess skin before/excess skin after." Patients with loose or excess skin prior to surgery will usually have a worsening of the appearance of the skin post suction.These patients will typically be better served by skin excision procedures.
Beware of stretch marks as these are the hallmark of skin with poor inherent tonicity which is unlikely to "snap back." Older patients with older skin also do not retract as well as younger patients.
While there are modalities aimed at skin tightening (SmartLipo/Thermi), these are of limited effectiveness when there is more significant laxity.With regards to your specific question, the majority of the post operative changes occur in the first several weeks after surgery, however, a final result may take up to 6 months. I generally have patients wear compression for 4-6 weeks post op.Based upon your photos, you might consider an excisional procedure to address the skin laxity.
As always, discuss your concerns with a board certified plastic surgeon (ABPS).