I can answer for pc
- click the 'download now' button
- wait 'till it's done downloading the file
- go to files
- go to 'downloads'
- go to the zip folder of it
- then click the gacha neon
- extract it
- then go back out to downloads
- click the (unzipped ver.) gacha neon folder
- then click gacha neon
and that should do it