Hi how can I get gems help me get gems please

Dragon TV

Complete the Jewellem tower to get a gem a day.
Complete the leagues to get gems per league completion.
Dragon TV for daily videos for gem and other rewards.
If your account is high enough and if they are available complete surveys and tasks for "free" or low cost gems.
And as always gems are available in events in chests.

And of course you can always buy them in offers, the gem shop and the Piggy Bank.

I think I included the main sources of gems, I might have missed one or two.