the summoning jutsu itself can either be signed to summon a creature either with a tattoo or a scroll (most people choose the tattoo as it is easier) In the anime the user will bite their thumb or draw blood from somewhere on their body and perform a few handisgns and slam it on the ground and the creature will be summoned
here's the Jutsu
(Kuchiyose no Jutsu) - Summoning Technique
Rank: B
Type: Defense/Attack/Suplementary
Range: N/A
Chakra Cost: 20
Damage points: N/A
Description:
To summon the creature the ninja will wipe blood on his hand, perform the Boar → Dog → Bird → Monkey → Ram handseals and then touch the ground or another object, where a sealing formula will appear. Though it appears that as long as significant pressure is placed against the blood in some form, the summon will be complete, most summoning uses use a solid surface, though in some cases it can even be done mid air. There can be variations to the summoning steps, some ninja like Temari will wipe blood on her fan, then by swinging the fan the animal is summoned. Other ninja like Orochimaru wipe the blood across a snake tattoo on their arm first, then touch the ground. Others will clap their hands directly like Nagato through the use of his Animal Path. The user must have signed the contract with the creature he wants to summon but the technique can be used to summon a generic creature of that contract (B-Rank) which will have no special traits or abilities beyond those normal to the rest of the animals in the contract. The animal is always summoned on the mark that appears upon slamming the users hand or, if not the case, always in short range of the user.