1234 Rhythm Guitar

To get the rhythm part solid, yet groovy in '1234' you need to practice to a metronome, aim to place the 2nd and 4th beat later on the click than 1 and 3, which should be on.
This style of playing creates a lazy groovier feel that goes well with the bluesy vibe of '1234'.

Experiment with how much later you go and what this does to the groove.

The anticipated shuffled strums can also be manipulated into how close they are to the main strums.
Experimentation is the key here.

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Rhythm Guitar Is About Attention To Detail

Notice the slight difference in dynamics when the verse starts.
To aim to be as dynamic as possible in your playing, rather than relying on pedals and gadgets will make you a better musician, so as demonstrated here, constantly adapt your strumming to the vocal.

Use the DIY TAB for basic structure and rhythm, pairing harmony with melody line, dynamic changes and little variations are better left alone in the arrangement.

Instead, keep the dynamical aspects improvised, adapting to vocals and other instruments.
This type of approach is all about the right hand and will make you grow as a musician.

To never play the same thing twice will keep you in the music, an important step in order to let music come through you, rather than from you.