By right-clicking the collar it will go into your character's tool-slot in the profile. Cycle between weapon, collar and mining cell with TAB. Just get close enough to the creature that you want to tame until you see the green X. Use the collar on the creature as long as it needs while the green bar fills - from 10 seconds (non-aggressive surface-creatures) to 1 minute (corrupted creatures).
Taming Creatures Edit
Most creatures will not be happy with being tamed and will either put up a fight, move around and/or run away, so you will have to use different strategies to make them hold still and/or let your character survive the whole time you'll need for taming.
To safely tame creatures you can cycle them carefully like when fighting them, or stand on a ladder to tame them. Hitting creatures with a weapon or bomb additionally to taming will not be of any help! For more taming strategies, refer to the next section.
Keepas (and common green Leafies) will run away, so you will have to come up with different strategies for them. Leafis are slow runners and will often take a break, but to catch Keepas you can try to cage them in or lure them into pits (3 blocks high). Stun Bombs might be a very good idea too.
As soon as your pet is tamed, it will let hearts fly into your direction. You can right-click it or interact with it to open it's pet-window. Pets become immortal, so night creatures or cave creatures will not burn in sunlight as Pets. Currently there seems to be no limit of pets you can have.
Best would be to make your new Pet follow you now - ideally to some secluded area so it won't wander off from there, and you will be able to find it again quickly. When outdistanced while following, Pets will teleport to you, they can follow you through teleporters, and can also teleport to your touchstone with you. Except for rare occasions when bugs might hit and make Pets stop following you - they will usually return to where you have tamed them in this case and still be marked as being your pets.
After reaching your corrall, always set Pets to "Stay"!
Note that if you have multiple pets you may press "Y" to set all nearby pets to "follow" you and "I" to set all nearby pets to "stay". This works when you need to relocate large numbers of pets and want to save time from individually clicking them and setting their statuses. Additionally, if your pets are scattered too far and wide you may also use these commands to gather them in with ease.
Currently a bug can make Pets vanish - or occasionally return to where you have tamed them - if they are set to "Wander". Very rarely Pets that were told to "Stay" can even be set back to "Wander", so if you see them moving, you should quickly tell them to "Stay" again.
Pets can also be dressed with a Hat and/or a Bow if you like and have already found some. Your Pet can be dismissed anytime. It will then vanish after leaving a Loot Bag containing whatever usual loot this creature would normally drop if being killed.
Maintaining Pets Edit
After taming, you will want to feed your Pet (Pets given their favorite food will yield the best harvest), then harvest from it when ready (no specific power cell needed) and afterwards clean it with a Washer. This cycle can be repeated as many times as the owner wants, hence making taming an effective strategy to obtain loot from creatures without having to hunt and fight them. To feed pets who prefer cooked food like sandwiches and soups, crops and food must be grow and cooked with the use of a Cooking Station. Different pets will have different favorite foods, so if you tame a pet and are unable to craft its favorite food due to certain ingredients being hard to access (E.g. Chizzard Egg if you have yet to tame a Chizzard), you may want to consider dismissing the pet and taming one that is easier to feed. To craft the Washer you will need Obsidian bars.
Taming Strategies Edit
There are a variety of taming strategies formulated by players over the course of the releases. As of R40 (March 2017), there are a few main ways to create simple to more complex structures to tame creatures while getting hurt minimally (or not at all).
The simplest strategy for the most mobile taming trap would be to create a diagonal line of blocks on the ground, so that your final structure would look like the path a Bishop travels on a chess board. (See below)
After the base layer is done, leave the second layer empty and finally build a top third layer exactly above the first initial layer. (See 2nd screenshot). You should now have a situation where the first and 3rd layer is exactly the same, with an empty 1 block space as the 2nd layer.
All you have to do now is lure a creature towards you and sprint around the side of the structure fast enough to trick the creature's AI into walking into the structure from the other side, creating a situation where you are on one side and the creature is on the other (see 1st screenshot). If the creature follows you, fret not and just circle the structure until you are in the situation as listed above.
Finally, walk towards the intersection of your structure so the creature will come close to you. BE CAREFUL, as staying there will allow the creature to hit you! Once you have lured the creature close enough, place a block (new block) in that intersection so the creature may not reach you but you are able to tame it. (see 3rd screenshot).
From there, the creature will not be able to hit you but you will be near enough for you to tame it. For smaller creatures like Pebble, Pigsy and Leafi who can fit through a 1 x 1 block space, it is advisable to place a slab on the bottom part of the 3rd layer. This will create a "half-block" hole through which you can tame the creature, but the creature will not be able to fit through.
If you encounter situations where the one block space is too large and you are being hit through the space, placing slabs on the bottom the top layer will usually do the trick to help save you from the attacks. This strategy works if you wish to tame while travelling and for creatures that will aggro if you approach them/attack them.
Refer to the Gaps subsection under the Things page for various other traps and structures you may use for taming. Additional advanced taming strategies involving block phasers and sensors will be added in due course.