Colton gave away 4 stickers * 3 friends = <<4*3=12>>12 stickers.
Colton gave Mandy 2 + 12 stickers = <<2+12=14>>14 stickers.
Colton gave Justin 14 stickers - 10 = <<14-10=4>>4 stickers.
In total, Colton gave away 12 + 14 + 4 stickers = <<12+14+4=30>>30 stickers.
Colton's number of total stickers at the end is 72 - 30 = <<72-30=42>>42 stickers.
#### 42