Stock market investments are a way to quickly earn or loose money. There are people who buy a sinlge share or thousands of shares. There is no minimum or maximum as long as the amount in a legal source of income.
1.Basic requriments (knowledge)
The knowledge of how to buy stocks - based on the brand, its service, its supply and demand equation, its debt and it's future progress.
To start with, I would suggest focus of large cap stocks, the returns are not very high but they can tolerate market ups and down better. Please follow a few stocks, Inofsys, Maruti,ITC etc for a few weeks
2.Tools to invest
You need a demat account, it can be given by the bank themselves or their are lot of stock trading companies who do it on your behlaf
Negotiate for a good Annual Maintenance charge, T+3 or 4 days to settle account (you get 3 days to pay the money after the day which you buy). You have JM financials, Kotak securities, Sharekhan or Motilal Oswal.
You would need an active bank account, proof of I.D, address,income,residence and age.
You can do it online or they come home with the forms. Initially choose only for stocks, do not try out futures/commodities/forex these are very volatile
3.How much money- Although there is no limit for legal purpose, you have analyse your own resources. Normally for a salaried employee about 10-20% of the montly savings can be used. If your risk is less, stick to this because, in the event of a loss, you would not loose sleep over it.
4.Single or multiple companies?
There are people who buy3-4 shares regularly over a period of time with excellent knowledge of the company and made good money. There are also people who by a basket of 5-10 shares and over a short period made good money. So, it depends on what is your time frame, are you trading to make a regular monthly income or use the stocks like a MF on a long term basis.
Some people have multiX stocks ( stocks that literally multiply over a period of time). You can check Sanwaria Cons, Godavari Power, Tata Steel etc.
5. Single or bulk?
It is always not wise to buy in bulk. You can see for each stock there would a 'Block Deal' worth crores listed, these would be the high players, fund houses who buy with a long term horizon.
You have to expect the unexpected in the stock market. For instance PC Jewellers, opened this moring at 486, around 10:30 AM fell to 195 and then now it's back because of a new that could potentially affect its growth. There has been a Block Deal of 2L shares worth 6.36 crores. For a retial investor, what happend today would have sppoked them, but for a large fund house this has been a good oppourtiny.
Start slowly, be careful of the amount and when you invest, any news (quarterly results, government policy, sentiments, news that has a major impact on the order books or raw materials) that can affect the company, reflects on the share price, so you need to be watchful.
When your stock has done very well you can do what most do, book partial profits( if you have 100 shares of X, you can sell 50-75, get the profits in hand and then invest the principal into another good company). If the share is performing poorly, then you have a choice of holding it, averaging the price ( buy more so that your average price becomes lower) or book losses. All these needs time, patience and effort.