a) I’ve got a lump sum I could invest
b) I’ve got some spare money each month I could invest
c) I’ve got a mix of the two
Investing a lump sum can work well over a longer period (five years or more is usually recommended although you can choose to sell investments at any time). You can expect ups and downs along the way but holding investments for longer means more potential for their value to go up by the time you come to sell them.
Regularly investing a smaller amount is another way to get started and can be good for building your confidence. By investing gradually in smaller chunks, you spread your risk of being affected if investment values go down. In fact, you can even benefit from this as your monthly investment amount will buy more when prices are low.
Whichever option you choose, or if you choose a combination of both, you should be prepared for the risk that you might get back less than your original investment.
If you’re not prepared to take that risk, or can’t realistically afford to, given your personal financial situation, you may not be ready to invest.