The first thing you need to understand that it's not just a matter of the majority of miners for a hard fork.... it's got to be pretty much everybody. Otherwise, you will have a blockchain split with two different user groups both wanting to call their blockchain "bitcoin". Unspent outputs at the time of the fork can be spent once on each new chain. Mass confusion.
The only way to do it is to get most major clients to accept larger blocks AFTER a future specified date.
That way once say "2017 Dec 31" rolls around 90% of BTC users will all accept larger blocks at the same time and the confusion will be minimal.
This is not that hard honestly just get MyWallet, Armory, the Satoshi client and Electrum programmers/distributors to agree on a date say "2020" and a new limit "100mb" and you're done.
I don't see why that many people would reject this change and as such the new standard should be rolled out way before it takes effect.
Miners are irrelevant in this, but they should welcome the change; BTC will never grow if normal people can't use it. We would be right back to trusting banks, only backed by BTC instead of gold this time. We all know what a wild success THAT has been!