Trapping is the most effective means of mouse control. But it is only effective after the whole house has been mouse-proofed: that is, all possible mouse entry holes have been sealed shut with steel repairs. It is pointless to begin a mouse trapping program if the house has not been sealed shut. First of all, new mice will continue to enter the house indefinitely as long as they can find open entry holes. Second of all, it is far easier to trap mice once those holes have been sealed shut. Mice are creatures of habit, travelling the same pathways over and over again - like mice in a maze! Once their normal exit/entry holes into the house have been sealed, they change their behavior and seek alternate territory, and seek alternate food. They are far easier to trap at that time. But what type of trap to use? You can purchase several styles and designs of mouse trap. There are many types of snap traps, electricution traps, live cage traps, repeating live traps, glue traps, and so on. This site is focused on humane treatment of animals and effective solutions to problems. There is no way to humanely trap mice in live traps. If you block them out of your house, they are done for. They will not survive more than a few days outside, and will be eaten by predators. So it's pointless to live-trap them. It's also incredibly inhumane to use glue boards. Read about inhumane glue boards. The best trap is actually the old standard wooden snap trap. I prefer Victor brand. I have tested over 14 types of mouse traps so far, and nothing is as effective as these original wooden snap traps. They can be set in high numbers, on the mouse runways, the flat bottom holds them steady in insulation, and the pan tension can be adjusted to hair trigger. Nothing is better. Remember, the key to successful trapping is in sealing shut the house first, then in placing the traps directly on the mouse runways second. Bait is of least concern - peanut butter, or a variety of foods, work fine. You actually don't need any bait at all. Read more about mouse trapping and about the best type of mouse bait.
Location is key - inspect inside the attic for mouse paths - runways and tunnels in the insulation, marked with droppings. Set the traps in these areas of high activity.
I've tested at least a dozen different types of mouse trap in my career, and absolutely nothing is more effective than the old standard wooden trap with the yellow trip pan.
Yes, you can set traps near the primary entry hole into the house if you want. I rarely do this, because it's better to just seal the holes, but it can be an option.
Mouse Trapping Tip #1 Don't bother to set traps until every last entry hole into the building is sealed shut first. If openings remain, trapping is futile, and will never end.
Mouse Trapping Tip #2 Use the original wooden Victor snap traps - there are two varieties, one with a small metal trip pan and one with a large yellow plastic trip pan. Use the yellow plastic one. It has a higher catch rate and can be set more easily, with hair-trigger sensitivity.
Mouse Trapping Tip #3 Bait the traps with peanut butter, smeared on the yellow pan. But truth be told, if you set the traps in the right location, you don't even need bait. But it does help a bit.
Mouse Trapping Tip #4 Set the traps in areas of high mouse activity - it's easy to spot in the attic. Just set the traps amidst all the droppings and mouse paths you see.
Mouse Trapping Tip #5 Check the traps often, at least every other day. This will keep you apprised of how the mouse control project is going. In addition, you don't want to leave a dead mouse on a trap for too long, because it will start to decompose and attract flies and cause a tremendous odor.
Mouse Trapping Tip #6 You can stop trapping after you catch no more mice and hear no more noise. If you've sealed the house properly, you will catch all the mice within 3 days or less. If you failed to seal fully, then you'll keep hearing mouse noise, which means you've got to inspect again and find the rat entry.
Trapping mice in the attic. Remember, do not set cage traps inside the attic. Mount traps to the entry/exit holes, or set cage traps bolted on the roof, in the shade. But the best strategy of all is to not even trap the mice at all! The use of a one-way exclusion door is usually the best, the easiest, and the most humane method. You can trap mice in the attic if you follow the correct approach. Best of luck!