If you want to add liquidity to the market, place limit orders.
Here's an example of the PrimeBit order book.
On the right side of the Order book, choose "BUY", then Type "Limit" order type, set the "Quantity" (number of PrimeBit contracts), and activation price, which will be 20803 in our case (the highest value on the buy-side in the order book) or lower. Double-check the order details and tap the "BUY" button at the bottom of the new order component.
The order is now visible in the "Pending Orders" tab and awaiting execution.