Algorithmic trading is just automating a defined set of rules through a broker's API. Here's the honest beginner path — in order, because skipping steps is how people lose money fast.

1. Get a broker with an API

You need a retail broker that lets software place orders. Alpaca and Tradier are common choices; both are fully legal for individual traders (is algo trading legal, Alpaca vs Tradier). This is the plumbing everything else runs on.

2. Define one simple strategy

Start with a single, clear rule set: an entry condition, an exit, a stop, and a position size. Simple and testable beats clever and vague. Write down exactly what it does before you code anything (what a trading plan is).

3. Backtest — honestly

Test the rules on history, but avoid the traps that make dead strategies look alive: look-ahead bias, curve-fitting, and ignoring costs (backtest vs forward test, overfitting).

The goal of a backtest isn't to find a strategy that looks perfect. It's to find one whose flaws you understand before they cost you real money.

4. Paper trade, then go live tiny

Run it on a simulated account first to catch bugs and behavior a backtest can't (paper trading). Only when it behaves live do you switch to real money — at the smallest size you can, non-custodially, in your own account. Scale only after it earns your trust.