If you play through the game normally you will get this easily.
But, if you used the cheat codes to get the other achievements (see the achievement guides for:
The Heart of Gold achievement in Rare Replay worth 106 pointsSolar Jetman: Collect all pieces of the Golden Warpship over time.and don't want to run the entire game, or at least half of the game, for this one achievement here's what you can do!;
Simply load up the first mission, grab the very first item in the game (just go to the left and then down, then when the path branches you can either go left, or right. The ship part or the gem will both work for the achievemet), grab the item and bring it all the way to your ship. From here, make a save right before you drop the item in your ship, drop the item in, load and repeat! I just tested it literally in the last 5 minutes and it works like a charm!
The item I used (on the left path) is a blue diamond about the size of your ship.
Here is a picture of what it looks like:
Alternatively you can use the gems scattered throughout the level. The first one is the right path of the fork, pretty much directly below the start.
Here is a picture of what they look like:
If you don't want to do this, the game is actually kind of fun, so just play through the game!