> ## Documentation Index
> Fetch the complete documentation index at: https://docs.saucerswap.finance/llms.txt
> Use this file to discover all available pages before exploring further.
# Trade on the order book
> Learn to trade on SaucerSwap V3: read an order book, choose a market or limit order, review token permissions and fees, sign, and check your fills.
Use the **trade** page to buy or sell tokens on SaucerSwap V3's central limit order book (CLOB). A market order seeks an immediate fill at available prices; a limit order lets you choose a price. Unlike [V1 and V2 liquidity positions](/protocol/overview), a V3 order offers one token for another without depositing into a pool.
## Prerequisites
* A connected [Hedera wallet](/get-started/wallet) with the token you want to spend
* Enough [HBAR for network fees](/get-started/hbar) when associating tokens or granting permissions
* An understanding of the [V3 order book risks](/legal/orderbook-risk-notice)
## Read the market
The first token in a pair is the base token; the second is the quote token. In HBAR/USDC, **Buy** spends USDC to receive HBAR, and **Sell** spends HBAR to receive USDC. A price of 0.08 means 0.08 USDC per HBAR, not the reverse.
| Surface | How to use it |
| ----------------------------- | -------------------------------------------------------------------------------------------------------- |
| Market selector | Choose the token pair you want to trade |
| **Order Book** | Read resting bids (buyers) and asks (sellers); the difference between the best bid and ask is the spread |
| **Recent Trades** | Review completed trades; the last price is historical, not a quote for your order |
| **Price Chart** and **Depth** | Compare price history with the available order-book liquidity |
| Order entry panel | Choose **Buy** or **Sell**, the order type, and your price and amount |
Larger orders may reach several price levels. Check the [market's trading increments and minimum order size](/protocol/saucerswap-v3/markets#market-parameters), and use the settings currently shown in the app.
## Set up trading permissions
Open [the trade page](https://www.saucerswap.finance/trade), select a pair, and connect your wallet. Review and accept the V3 terms when prompted.
Follow the wallet sign-in prompt to authenticate your account. This off-chain signature does not move tokens and is separate from placing an order.
The app guides you through token association and any missing token and reactor permissions when you place your first order for a token. The reactor is the contract that settles signed orders. Read the spender and allowance in each wallet prompt; setup transactions can cost HBAR.
Token permissions are standing allowances, not permissions limited to one order. They can authorize maximum amounts until revoked. The order signature separately sets that order's trade parameters. See [managing V3 orders](/tutorials/manage-v3-orders#review-standing-permissions) for reviewing or revoking allowances.
## Place a limit order
A buy limit sets the highest price you accept; a sell limit sets the lowest. A limit order can fill immediately if it crosses an available price, or rest until a matching order arrives. Choosing **Limit** does not automatically make every fill a maker fill.
Select **Buy** or **Sell**, then **Limit**. Enter **Price** in quote tokens per base token. The **Mid**, **Bid**, or **Ask** shortcuts populate a reference price; review it before continuing.
Enter **Amount** and check the token shown beside the field. Choose an **Expiry** appropriate for how long you want the order to remain valid. An unfilled limit order does not stay open indefinitely.
Enable **Post-Only** if you want to add liquidity without immediately taking an existing order. An order that would cross the book is rejected rather than filled as a taker. Leave it off if you are willing to trade immediately at your limit or better.
Check the pair, side, price, amount, expiry, **Order Value**, and displayed fee or rebate. Complete any setup prompts, then sign the order in your wallet. A signature submits your instructions; it does not guarantee a fill.
Review **Open Orders** and **Closed Orders** below the chart. An order may fill in parts, with the remainder staying open until filled, canceled, or expired. See [how to track and cancel orders](/tutorials/manage-v3-orders).
## Place a market order
A market order seeks available liquidity now. Its estimated average price may differ from the last trade, particularly in a thin book. It can fill partially or fail; it does not guarantee a complete trade.
Select **Buy** or **Sell**, then **Market**. Enter **Amount**, checking the input token and available balance.
Review the estimated result, displayed fee, and available depth. If the app reports insufficient liquidity or an order below the minimum, adjust the size or consider a limit order. For the difference between a quote and execution, see [slippage](/get-started/faq#what-is-slippage).
Complete any required setup and sign the order. Check **Open Orders** and **Closed Orders** for the final status and actual fills before placing another order. Unspent tokens remain in your wallet, but an order can remain active briefly while matching and settlement complete.
Fees depend on the market and your maker or taker role. Holding xSAUCE can affect your fee tier; maker rebates are subject to a cap. Use [V3 fees and rebates](/protocol/saucerswap-v3/fees) to understand the calculation, then review your current account's fee in the app.
## Next steps
Track partial fills, cancel orders, and review standing permissions.
Understand matching, settlement, and liquidity on an order book.
Read market settings and minimum order requirements.
Use a quoted swap without managing a resting order.