Thanks to warfaremachine so showing me how to do it once.

It's actually very easy to do so I will use one of WFMs models that being Lop

So to do this on these models specifically its very easy to do in a few steps

1. Load in Lop and her outfit (you will know what it is when you type in "lop")

2. Make sure "Lop bis" is at the top of your list

3. Drag Lop's model name onto the outfit's model name.

4. simply click and hold the "Zero" flex slider and drag it the right all the way and you're done!

Extra step. in some cases you will run into models with outfits that get clipped or just screw up locking into the model and makes it look odd.

So just in case this happens there is an easy fix. First hit "ctrl + Z" to undo what you did when using the "Zero flex slider".

Then just simply hit the "+" button on the outfit and make sure you have "hidden" shown in the list if not just right click an empty space and click "show hidden tools"

Finally just look in the "unknown" area of the outfit you will see some parts or "bones" without a "lock" symbol so while holding "ctrl" just left click to unhighlight the unlocked bones and make sure you have selected all the other bones on the outfit along with making sure you do not have the "unlocked" bones highlighted then use the Zero flex and your done.

hope this little tutorial helps all of you out.

Thanks to WARFAREMACHINE for showing me how to do this before.