What reason do you have to believe you can make money day trading a $30k account? You're almost certainly wrong and will either blow up your account if you have poor risk control, or slowly bleed down if you have excellent pro-level risk control.
If you insist on trying, you have basically 3 options - in descending rank order IMO:
1. Swing trade or speculate on long timeframes (several days to several months hold time)
2. Use a scanner to identify stocks in play e.g. large gaps, strong volume and direction in the first 15-30 minutes, and play those to catch a strong one-way trend day or a hard V-reversal move.
3. Watch ~10 futures contracts (stocks, energy, metals, ags, FX etc) and trade those offering the best setups (if any are) on a given day.
What you should avoid under any circumstances is what 99% of retail traders do - which is to head straight to the ES or NQ and try to scalp tiny moves multiple times a day, using chart analysis or guru methodologies like Al Brooks.