1. Consider how much, by tranches, you can put away over what time frames and will not likely require to access.
2. Having allocated your funds into the time horizons consider appropriate investments for each tranche. The longer you can commit the funds the more investment opportunities should be appropriate for that tranche e,g if say a two year window then shares probably not appropriate, if longer term, and considering current inflation, a bank deposit could in real terms erode your funds.
You need to have a mix, from ready funds, to slightly longer up the time window. e.g. I never buy shares if I think I might need to sell them within seven years, other people might say five years for shares, others maybe ten.
Once you think through your likely needs the investment decisions ought to become more obvious- if in doubt take advice but try to take it from someone you trust who knows what they are doing. ( I had my Dad to initially advise me and have learned from experience thereafter)
Investment is a risk/reward equation, higher returns usually come with higher risk, spreading investment can sometimes mitigate risk, to a degree, but not always; so caveat emptor.
Word of warning- trading in and out of shares, unless you are really good at it/lucky, can seriously damage your wealth. If you are prepared to stick a tranche away in a portfolio of say investment trusts you can get a dividend yield of 4-5% net of tax, albeit with risk of prices falling but also with opportunity for prices to rise. The past figures for say £1,000 invested in shares for 50 years, with dividends reinvested ,is pretty stunning (past performance no guarantee etc)- the secret is never needing to sell into a weak market which means a long term horizon.