There are a million ways to make coins.

• play challenges, complete the objectives and achieve milestones
• Play CS/Hut champs
• Market watch, 59th minute sniper
• Buy “coins” online
• Buy a few hundred packs and quick sell the crap.

The easiest, but most costly method is the last one i mentioned. Within a few hours, you could have 300K — 1M in coins depending on how many packs you open.