Best way to pack customs for shipping?

[SunPony]

Its been years since I've shipped a custom, and I can't remember how I used to pack them in the box.  So I'm looking for recommendations!  Should I wrap it in white tissue paper?  An unsealed clear plastic bag?  A sealed plastic bag?  Printer paper?  Fabric?  Tissues?  Something else?  One of these customs is going out of the country, so its going to be in the box for probably multiple weeks as opposed to a few days...so I'm very concerned about that one.  And even for US ones shipping has been a bit unpredictable.  My customs are all sealed if that makes a difference.  And I'm not too concerned about the "filling" - I'll probably use packing peanuts or bubble wrap unless anyone has a better material they recommend.

What are your tried and true custom wrapping/packing methods?

Thanks in advance 

[ChocolateStarfire]

I would say make sure the sealant or paint is not tacky, and the sculpted parts, if any, are strongly attached. Then wrap the pony like a mummy in fabric--an old t-shirt or scraps will do--then wrap in bubble wrap, and tape the outside so that no water can get inside with a ton of packing tape. You can fill the box with packing peanuts if you have them, old newspaper works well for this too. I like to include a note along with my business card. If the pony is small enough for a mailing envelope, I would still wrap in fabric and make sure it is a bubble mailer. Write FRAGILE on the package somewhere before mailing, and I use Sharpie to write the address/labels. I hope your package makes it okay!

[tailrustedtealeaf]

I would worry about the fabric transferring dye onto the custom? Especially since we're still on the tail-end of big humidity season. Unless it's white fabric, of course. 
I'd say acid-free tissue paper is probably safe as well so long as the sealant isn't tacky. Printer paper is a bit stiff and I feel like it wouldn't protect the pony in the same way.

Write FRAGILE on the package somewhere before mailing

I don't think this would make a difference, honestly. Pack for the worst, hope for the best.

[Griffin]

I'd say never use anything but plastic in contact with the custom - I've received a couple of sticky customs, which probably weren't sticky when they were packed so that's something to keep in mind. Peeling off tissue paper would be a nightmare. It's the same with fabric, even if it would come off easily, it could leave dust and lint behind. So either put the pony in a plastic bag or wrap it in bubble wrap if there are sculpted parts. The rest is up to you, colourful tissue paper can be a fun way to tie the box to a swap theme but newspaper will do just fine. Or packing peanuts, or air pockets, or more bubble wrap, whatever you have. (I'd prefer paper myself but unfortunately it's often heavier than plastic and I'm always struggling to keep the box within the weight limits so... at least all my packing materials are recycled from boxes I've received!)

Sometimes (esp. when there is delicate sculpting) I emulate the way toys are packed commercially: tie it to a piece of cardboard and place this inside a smaller box, making sure the "back card" is firmly attached.

[Roogna]

I use white tissue paper and bubble wrap. Always ship in a box, not an envelope. Make sure the box isn't too fitted (have room for more padding around the custom)

[ChocolateStarfire]

I hadn't thought of the fabric transferring dye to the pony--I haven't had an issue using rags or even chamois type material--that is something to consider!

[SunPony]

Thanks for all of your input!  Although there doesn't seem to be consensus    It sounds like lots of different ways work.