The past tense of nail one's colours to the mast is nailed one's colours to the mast.

The third-person singular simple present indicative form of nail one's colours to the mast is nails one's colours to the mast.

The present participle of nail one's colours to the mast is nailing one's colours to the mast.

The past participle of nail one's colours to the mast is nailed one's colours to the mast.