Minimum deposit amount on waves wallet is 0.01 BTC and you cannot send lower amounts to that. You can send waves or any of assets (token) directly to your wallet.
First send BTC to one of exchanges which support waves or any of token you want. Buy waves or any other token. Then withdraw from that exchange to your waves wallet.
To know which exchange support waves or a special token go to coinmarketcap.com and search for that .
Thanks. I already send 0.01 btc. I forgot I can't get waves in there as well without having atleast 0.003 waves already in my wallet. Managed to buy and made a thread in there with help of shapeshift instant exchange.
I swear, just a couple of months ago tho that I managed to deposit a 0.001 btc there. Faucets also give lower amount of waves. I kinda hate the dex now.