update docs

docs/usage.md

@@ -73,14 +73,20 @@ An [example samplesheet](../assets/samplesheet.csv) has been provided with the p
 
 ### Genomes input
 
-Magmap needs two mandatory input to run. One, the samplesheet, was explained above while the second, genome input needs to be specified with the option `--genomeinfo`. The file is a `.csv` file and it requires three columns: accnos, genomes_fna, genome_gff. it looks as follow:
+Magmap needs two mandatory input to run. One, the samplesheet, was explained above while the second, genome input needs to be specified with the option `--genomeinfo`. The file is a `.csv` file and it requires three columns: accno, genome_fna, genome_gff. it looks as follow:
 
 ```csv title="genomes.csv"
 GCA_002688505.1,https://github.com/nf-core/test-datasets/raw/magmap/testdata/GCA_002688505.1_ASM268850v1_genomic.fna.gz,https://github.com/nf-core/test-datasets/raw/magmap/testdata/GCA_002688505.1_ASM268850v1_genomic.gff.gz
 ```
 
 N.B.: you don't need to provide gff, Prokka can handle if you only provide fasta files but we reccomend when adding gff that the file is generated by using prokka in order to don't get any conflict with other generated gffs.
 
+```csv title="samplesheet.csv"
+accno,genome_fna,genome_gff
+GCA_002688505,./genomes/GCA_002688505.fna,./genomes/GCA_002688505.gff
+GCA_002688515,./genomes/GCA_002688515.fna,./genomes/GCA_002688515.gff
+```
+
 ### Other inputs (optional)
 
 Magmap can handle several types of input that can be used for different purpose.