Yes, there are various ways to increase your bag without trading. The surest for me though is staking. And you don't just stake for the sake of it. You've to choose a viable and trusted exchange or means to do so. I will recommend you carry that out on Binance exchange, hoping that it has the coins you've on staking. You can get this on Binance exchange home page. Click on "More", it directs you to another page where you can see "Staking" under finance. If this isn't clear to you, you can quote me and I will do a screenshot for you.