Everything flows into a spreadsheet I created that has a row for each month, and tracks my spending, income, and net worth. The data for each new row comes from a few different places.

Lunchmoney aggregates and categorizes my spending data.

My net worth is tracked in another spreadsheet that updates as asset prices change. This spreadsheet also tracks my asset allocation across my accounts, which is roughly based on the 3 fund portfolio from bogleheads (with a bit allocated to crypto as well) [0].

In terms of cashflow, I use Fidelity's cash management account, where I keep a buffer in a money market account. Income flows into this account, and bills flow out. They automatically liquidate the money market if I need more cash, which is nice.

And in terms of investing, historically I kept a 6 month emergency fund, then invested the extra every few months based on my desired asset allocation. More recently I have been increasing my cash cushion with the intent of paying off my recently purchased house in several years (since the interest rate makes it less attractive).

[0] https://www.bogleheads.org/wiki/Three-fund_portfolio