Yeah I don't want a failed deadly war like 1977.
The best way for a United Somalia is to first get somalia proper in order and make it developed whilst making sure somalis in ethiopia and Kenya become wealthy and armed so they do not become victims.
Inshallah after a couple of decades the Somali regions would be able to secede without too much trouble but this would heavily depend on support from a strong somalia which honestly would take decades to form.
A strong Somali lobby or ally group in neiboring countries would be helpful to the cause. If there is political interests they can promise and vise versa. Somalis should play politics the Ethiopian way. Dirty and pro Ethio but have a hidden agenda.