Not sure if this is a beginner's question, but it is fairly basic. I heard Dan Smith mention/insinuate recently on a stream that he uses a randomization method other than looking at a clock, and it made me wonder what the other types might be. The ones I'm familiar with are:

- number randomizer (online)
- watch/wall clock, divide sections into various degrees of aggressive/passive actions
- power suits, ex. Spade on high card always bets, diamond always checks, etc.
- positioning of cards, ex. If high hole-card is on the left, take aggro line, if high hole-card is on the right, take passive line, etc. (I saw Galfond do this while playing HU vs Bill Perkins on stream).

Any others?

A watch/clock is probably the most efficient and easiest so why go with any other method.

In addition to the ones you mentioned, here are two of many others that are possible:

A table of random numbers. If I remember correctly there was a book published with a million random numbers.

Coin flip: 1 coin for 50/50; 2 coins for 25% (HH), 50% (HT or TH), 75%(TT), 3 coins for 1/8, ¼, etc.

Interesting, though I can't imagine either of those being practical at a live poker table. Online I suppose you could (but then better to just use an online randomizer).

Just use an RNG website on your phone or an app

I'm not sure how helpful this is, but if it is between 2 decisions you can use colors on the flop. More red cards out is 1 decision and more black cards out is the other.