Carry all the necessary stuff in a seat pack -- spare tube, patch kit, multitool, tire levers, CO2, etc. And carry a pump on the bike.
I'm sure others will add to this list.
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The Lord is merciful and gracious, slow to anger and abounding in steadfast love. - Psalm 103:8
I am a cyclist. I am not the fastest or the fittest. But I will get to where I'm going with a smile on my face.