I printed the Gravity Ski Mount:

https://www.printables.com/model/651094-gravity-ski-holderski-rack-updated/comments

When it came time to glue the rubber on, I found it difficult to get it glued on flat and even.

I designed and printed this assembly aid.  Using 2 C-clamps or spring clamps, you can get even pressure while the glue is curing.

I used Shoe-Glue - an excellent flexible adhesive, meant for shoe repair:

https://www.amazon.com/-/es/110011-Zapato-goo-tube-transparente/dp/B002L9AL84/ref=sr_1_7?adgrpid=157790276396&dib=eyJ2IjoiMSJ9.aeTHYRlZtFsxpkplm9X5TieDQuKBXagxjetTvroz71K_TBRqg7Bs-ZUhYr8eeCHQBfjNAfm9axA6oB6pMojvtVPpRJOcZKkoh0flzA2IDPkpwmvTGtWWnJnQkrSDsmxBVZnxgV6WGpabNyLFPkc7SR_eybbYXtiNqNEeHsXU5cuBNgbh57zmARG2zOvGdwKl1YqmDE9cz_bi8aj-UPAtRnqOmX95G0jmtrv5dkEQK0ikHZz_h7dMlXZVJFlCiyyntvnC6A3-njugSb9BSKrOxxO2LRyz9meczKpzfycN8Ks.T1PPRNdBsFWujtx7hERwvOFM6p4ivnFkjH4hb_rwDgY&dib_tag=se&hvadid=687642076231&hvdev=c&hvlocphy=1003659&hvnetw=g&hvqmt=e&hvrand=17815068937526893270&hvtargid=kwd-461766461&hydadcr=21726_13375370&keywords=shoe%2Bglue&mcid=01ae313ce9bc3a2395b20118ef392473&qid=1748287804&sr=8-7&th=1