What are the cons of placing a huge order for Intraday Trading?

It depends on whether you are buying for long term or for intraday/short term.

For long term i.e more than 1 year, huge order placing in single day does not matter because in 1 year there can be very large movement in price upwards or downwards.

But for intraday/short-term if you place very large order in single day it can change the price very much.And there can be losses when you exit your previous position.

Ex- price movement occurs due to demand and supply. If for stock A, price is 1000, your huge order can move the price say 20 points up, then the price becomes 1020. This price change is mostly due to your demand. So when you try sell your shares at 1020 it will not get executed at 1020 when you place limit order because there are no buyers at 1020 for such huge order. So you place a market order to sell, then price reverse back to 1000 or more lower. Thus you can incur losses. Thus it is recommended for intraday trades that such quantity should be traded which you can exit very easily.

Split the order into number of small units of limit order

Say you are buying 5000 shares, buy 1000 shares each time and use disclosed quantity as say 200.

For example u want to buy at 800, limit order, only may be 500 shares will execute, remaining 500 may not execute and price could have moved to 801 say (not because of you, but because of your normal price movement), then wait for few seconds to see if price comes down, then again place 1000 shares with disclosed quantity 200 as limit order.

Even if price has moved slighly up, dont worry, modify your limit order to say 801 or something as per best available price (Best Ask rate) in the ticker window, and pending amount of shares also will execute.

If you are buying in a hurry, say as per sudden breakout or spikes, then limit orders wont work, you can use SL-M orders to trigger buying at market rates, in this case try to refrain the number of shares to 2000 or something in a single shot.

Thanks Ekansh for ur answer.