say a clanmate starts a rally against an enemy, and you want to help. 1.) Do I click on that enemy and click “rally” too, or? 2.) Also, does it matter if the enemy being rallied against has much higher stats than I do? Will my troops even be helpful for my clanmate in that case?
Tap the flag that shows marches and you will see a "Rallies" tab. Tap the rally you want to join (under clan, not enemy) and you'll see the option to join. (make sure it's not 8 hours long or some other long rally... you'll be stuck in it unless the leader cancels, so be sure to pay attention, especially since it costs some gems to cancel. Yes, your troops are helpful too. Get a rally leader with decent dragons, allies and a leader rally cap. Send your guys and they can help, especially if your clan struggles to send enough troops to fill a rally. Some troops are better than none.