Socks, bags and the rest of the kit

Cleats, ball, shin guards — those get researched. Socks and bags get grabbed off a shelf, and then cause most of the small weekly friction of youth soccer: guards that slide, a bag with wet kit fermenting in it, a jersey that turned out to be two sizes small.

Socks do a real job

A soccer sock is not decoration. In slip-in shin guards it is the only thing holding the guard in place, which makes sock choice a protection decision rather than a comfort one. A stretched-out sock is the most common cause of guards migrating round the leg mid-game.

Buy over-the-calf, with real compression through the calf, and buy three pairs rather than one — soccer socks get soaked, and nothing is more predictable than needing clean ones on a Saturday morning. The adidas Copa Zone is the long-standing default because the cushioning survives repeated washing and the calf grip is genuinely tight. Nike's Classic II is cheaper with a wider color range, which matters when a team has specified a sock color. See the sock picks.

Grip socks — the thin inner socks with rubberized pads — are a separate product and a genuine one. They reduce how much the foot slides inside the cleat, which is a real cause of blisters and of losing a first touch. They are also expensive, worn under the team sock, and largely wasted on a kid who plays once a week. Are grip socks worth it works through when they are.

A bag's one job is separating the cleats

Everything else a soccer bag claims to do is secondary. Wet, muddy cleats in with a change of clothes ruins the clothes and keeps the cleats wet, which is how uppers rot. A bag with a dedicated shoe compartment fixes that, and a bag without one never will.

The second consideration is size, and this is where most bags are bought wrong. An adult team bag on a nine-year-old reaches below their hips and drags — get the junior size. Nike's Academy Team backpack is sized for a child and separates the cleats, which covers the basics. adidas's Tiro bag adds a ball compartment, which is the right choice if carrying the ball is your actual problem. See the bag picks.

Jerseys run small — plan for it

Soccer jerseys are cut athletically, which in youth sizing means slim and short. adidas's youth range in particular runs small, so a kid who is a comfortable medium in everyday clothes is often a large in a jersey. If they are mid-growth-spurt, size up — a jersey that rides up is worn once and then refused.

For practice, a plain jersey like the adidas Entrada 22 is what most rec clubs use, because it takes numbering and printing and costs little enough to own two. Buy two: back-to-back practices and a single jersey do not combine well. See the practice jersey picks and the jersey sizing guide.

Buying for someone else's kid

Soccer gear is a good gift and an easy one to get wrong, mostly because the two obvious choices — cleats and a jersey — are the two things you cannot buy without knowing a size. The things that work are the ones that fit anybody: a ball in the right size for their age, a bag, a rebounder, a pump.

• Best gifts for youth soccer players — by recipient and by what you actually know about them.
• Youth soccer gifts under $50 — the budget tier, without the tat.

The things you will forget

In rough order of how annoying it is to discover you do not have one: a ball pump, a water bottle that survives being dropped, a spare pair of shin guards, and a plastic bag for wet kit. None costs much. All of them are what separates a calm Saturday morning from a frantic one.