It's important when handling contacts in general to not have any oils on your hands, but with scleral lenses, it's doubly important, in order to avoid debris and fogging.
Ocusoft makes a very popular soap for this purpose, but I like to offer choices (especially budget-friendly ones), so I picked this one up from Hilco in spring 2018 to round out our lens handling collection. This is a nice slim travel-friendly 1oz squeeze bottle, which personally I find a little easier to use than the flip-top type. Unfortunately, I have not yet been able to get a detailed ingredient list (funny how hard those can be to come by sometimes) but I will post it when I get it.
If you like this, let me know, and I'll start stocking the larger size (10oz).
Leader Optical Hand Soap is oil and fragrance-free, specially formulated to clean hands prior to handling contact lenses; leaves up to 22 times less residue than ordinary soap.