diff --git a/Makefile b/Makefile
index 965b5c2..312eb99 100644
--- a/Makefile
+++ b/Makefile
@@ -15,8 +15,8 @@ tx:
 hash:
 	forge script script/HashData.s.sol
 
-sign\:%:
-	cast wallet sign --$* $$(cat data/hashData.txt) >> data/signatures.txt
+sign\:%: hash
+	OUTPUT=$$(cast wallet sign --$* $$(cat data/hashData.txt)) && if [[ "$$OUTPUT" =~ "^0x" ]]; then $$OUTPUT >> data/signatures.txt; fi
 
 simulate\:%:
 	forge script script/ExecTransaction.s.sol --$*
@@ -25,9 +25,10 @@ exec\:%:
 	forge script script/ExecTransaction.s.sol --$* --broadcast
 
 clean:
+	mkdir -p data
 	cp data/template.json data/tx.json
 	> data/hashData.txt
 	> data/signatures.txt
 
 
-.PHONY: contracts test coverage
+.PHONY: contracts test coverage hash sign simulate exec clean